Tech ENABLE_OPENGL_ES - Use OpenGL ES context - 1st installment

resources/shaders/ES/background.fs

@@ -0,0 +1,13 @@
+#version 110
+
+precision highp float;
+
+uniform vec4 top_color;
+uniform vec4 bottom_color;
+
+varying vec2 tex_coord;
+
+void main()
+{
+    gl_FragColor = mix(bottom_color, top_color, tex_coord.y);
+}

resources/shaders/ES/background.vs

@@ -0,0 +1,12 @@
+#version 110
+
+attribute vec3 v_position;
+attribute vec2 v_tex_coord;
+
+varying vec2 tex_coord;
+
+void main()
+{
+	tex_coord = v_tex_coord;
+    gl_Position = vec4(v_position, 1.0);
+}

resources/shaders/ES/flat.fs

@@ -0,0 +1,10 @@
+#version 110
+
+precision highp float;
+
+uniform vec4 uniform_color;
+
+void main()
+{
+    gl_FragColor = uniform_color;
+}

resources/shaders/ES/flat.vs

@@ -0,0 +1,11 @@
+#version 110
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+
+attribute vec3 v_position;
+
+void main()
+{
+    gl_Position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
+}

resources/shaders/ES/flat_clip.fs

@@ -0,0 +1,17 @@
+#version 110
+
+precision highp float;
+
+const vec3 ZERO = vec3(0.0, 0.0, 0.0);
+
+uniform vec4 uniform_color;
+
+varying vec3 clipping_planes_dots;
+
+void main()
+{
+    if (any(lessThan(clipping_planes_dots, ZERO)))
+        discard;
+
+    gl_FragColor = uniform_color;
+}

resources/shaders/ES/flat_clip.vs

@@ -0,0 +1,23 @@
+#version 110
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat4 volume_world_matrix;
+
+// Clipping plane, x = min z, y = max z. Used by the FFF and SLA previews to clip with a top / bottom plane.
+uniform vec2 z_range;
+// Clipping plane - general orientation. Used by the SLA gizmo.
+uniform vec4 clipping_plane;
+
+attribute vec3 v_position;
+
+varying vec3 clipping_planes_dots;
+
+void main()
+{
+    // Fill in the scalars for fragment shader clipping. Fragments with any of these components lower than zero are discarded.
+    vec4 world_pos = volume_world_matrix * vec4(v_position, 1.0);
+    clipping_planes_dots = vec3(dot(world_pos, clipping_plane), world_pos.z - z_range.x, z_range.y - world_pos.z);
+
+    gl_Position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
+}

resources/shaders/ES/flat_texture.fs

@@ -0,0 +1,12 @@
+#version 110
+
+precision highp float;
+
+uniform sampler2D uniform_texture;
+
+varying vec2 tex_coord;
+
+void main()
+{
+    gl_FragColor = texture2D(uniform_texture, tex_coord);
+}

resources/shaders/ES/flat_texture.vs

@@ -0,0 +1,15 @@
+#version 110
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+
+attribute vec3 v_position;
+attribute vec2 v_tex_coord;
+
+varying vec2 tex_coord;
+
+void main()
+{
+	tex_coord = v_tex_coord;
+    gl_Position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
+}

resources/shaders/ES/gouraud.fs

@@ -0,0 +1,89 @@
+#version 110
+#extension GL_NV_fragdepth : enable
+
+precision highp float;
+
+const vec3 ZERO = vec3(0.0, 0.0, 0.0);
+const float EPSILON = 0.0001;
+
+struct PrintVolumeDetection
+{
+	// 0 = rectangle, 1 = circle, 2 = custom, 3 = invalid
+	int type;
+    // type = 0 (rectangle):
+    // x = min.x, y = min.y, z = max.x, w = max.y
+    // type = 1 (circle):
+    // x = center.x, y = center.y, z = radius
+	vec4 xy_data;
+    // x = min z, y = max z
+	vec2 z_data;
+};
+
+struct SlopeDetection
+{
+    bool actived;
+	float normal_z;
+    mat3 volume_world_normal_matrix;
+};
+
+uniform vec4 uniform_color;
+uniform SlopeDetection slope;
+
+uniform bool offset_depth_buffer;
+
+#ifdef ENABLE_ENVIRONMENT_MAP
+    uniform sampler2D environment_tex;
+    uniform bool use_environment_tex;
+#endif // ENABLE_ENVIRONMENT_MAP
+
+uniform PrintVolumeDetection print_volume;
+
+varying vec3 clipping_planes_dots;
+
+// x = diffuse, y = specular;
+varying vec2 intensity;
+
+varying vec4 world_pos;
+varying float world_normal_z;
+varying vec3 eye_normal;
+
+void main()
+{
+    if (any(lessThan(clipping_planes_dots, ZERO)))
+        discard;
+    vec3  color = uniform_color.rgb;
+    float alpha = uniform_color.a;
+
+    if (slope.actived && world_normal_z < slope.normal_z - EPSILON) {
+        color = vec3(0.7, 0.7, 1.0);
+        alpha = 1.0;
+    }
+	
+    // if the fragment is outside the print volume -> use darker color
+	vec3 pv_check_min = ZERO;
+	vec3 pv_check_max = ZERO;
+    if (print_volume.type == 0) {
+		// rectangle
+		pv_check_min = world_pos.xyz - vec3(print_volume.xy_data.x, print_volume.xy_data.y, print_volume.z_data.x);
+		pv_check_max = world_pos.xyz - vec3(print_volume.xy_data.z, print_volume.xy_data.w, print_volume.z_data.y);
+	}
+	else if (print_volume.type == 1) {
+		// circle
+		float delta_radius = print_volume.xy_data.z - distance(world_pos.xy, print_volume.xy_data.xy);
+		pv_check_min = vec3(delta_radius, 0.0, world_pos.z - print_volume.z_data.x);
+		pv_check_max = vec3(0.0, 0.0, world_pos.z - print_volume.z_data.y);
+	}	
+	color = (any(lessThan(pv_check_min, ZERO)) || any(greaterThan(pv_check_max, ZERO))) ? mix(color, ZERO, 0.3333) : color;
+	
+#ifdef ENABLE_ENVIRONMENT_MAP
+    if (use_environment_tex)
+        gl_FragColor = vec4(0.45 * texture2D(environment_tex, normalize(eye_normal).xy * 0.5 + 0.5).xyz + 0.8 * color * intensity.x, alpha);
+    else
+#endif
+        gl_FragColor = vec4(vec3(intensity.y) + color * intensity.x, alpha);
+		
+    // In the support painting gizmo and the seam painting gizmo are painted triangles rendered over the already
+    // rendered object. To resolved z-fighting between previously rendered object and painted triangles, values
+    // inside the depth buffer are offset by small epsilon for painted triangles inside those gizmos.
+    gl_FragDepth = gl_FragCoord.z - (offset_depth_buffer ? EPSILON : 0.0);
+}

resources/shaders/ES/gouraud.vs

@@ -0,0 +1,77 @@
+#version 110
+
+#define INTENSITY_CORRECTION 0.6
+
+// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+//#define LIGHT_FRONT_SPECULAR (0.0 * INTENSITY_CORRECTION)
+//#define LIGHT_FRONT_SHININESS 5.0
+
+#define INTENSITY_AMBIENT    0.3
+
+const vec3 ZERO = vec3(0.0, 0.0, 0.0);
+
+struct SlopeDetection
+{
+    bool actived;
+	float normal_z;
+    mat3 volume_world_normal_matrix;
+};
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat3 normal_matrix;
+uniform mat4 volume_world_matrix;
+uniform SlopeDetection slope;
+
+// Clipping plane, x = min z, y = max z. Used by the FFF and SLA previews to clip with a top / bottom plane.
+uniform vec2 z_range;
+// Clipping plane - general orientation. Used by the SLA gizmo.
+uniform vec4 clipping_plane;
+
+attribute vec3 v_position;
+attribute vec3 v_normal;
+
+// x = diffuse, y = specular;
+varying vec2 intensity;
+
+varying vec3 clipping_planes_dots;
+
+varying vec4 world_pos;
+varying float world_normal_z;
+varying vec3 eye_normal;
+
+void main()
+{
+	// First transform the normal into camera space and normalize the result.
+    eye_normal = normalize(normal_matrix * v_normal);
+
+	// Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+	// Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+	float NdotL = max(dot(eye_normal, LIGHT_TOP_DIR), 0.0);
+
+	intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    vec4 position = view_model_matrix * vec4(v_position, 1.0);
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(position.xyz), reflect(-LIGHT_TOP_DIR, eye_normal)), 0.0), LIGHT_TOP_SHININESS);
+
+	// Perform the same lighting calculation for the 2nd light source (no specular applied).
+	NdotL = max(dot(eye_normal, LIGHT_FRONT_DIR), 0.0);
+	intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+    // Point in homogenous coordinates.
+    world_pos = volume_world_matrix * vec4(v_position, 1.0);
+
+    // z component of normal vector in world coordinate used for slope shading
+    world_normal_z = slope.actived ? (normalize(slope.volume_world_normal_matrix * v_normal)).z : 0.0;
+
+    gl_Position = projection_matrix * position;
+    // Fill in the scalars for fragment shader clipping. Fragments with any of these components lower than zero are discarded.
+    clipping_planes_dots = vec3(dot(world_pos, clipping_plane), world_pos.z - z_range.x, z_range.y - world_pos.z);
+}

resources/shaders/ES/gouraud_light.fs

@@ -0,0 +1,14 @@
+#version 110
+
+precision highp float;
+
+uniform vec4 uniform_color;
+uniform float emission_factor;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+
+void main()
+{
+    gl_FragColor = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
+}

resources/shaders/ES/gouraud_light.vs

@@ -0,0 +1,45 @@
+#version 110
+
+#define INTENSITY_CORRECTION 0.6
+
+// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+
+#define INTENSITY_AMBIENT    0.3
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat3 normal_matrix;
+
+attribute vec3 v_position;
+attribute vec3 v_normal;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+
+void main()
+{
+    // First transform the normal into camera space and normalize the result.
+    vec3 normal = normalize(normal_matrix * v_normal);
+    
+    // Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+    // Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+    float NdotL = max(dot(normal, LIGHT_TOP_DIR), 0.0);
+
+    intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    vec4 position = view_model_matrix * vec4(v_position, 1.0);
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(position.xyz), reflect(-LIGHT_TOP_DIR, normal)), 0.0), LIGHT_TOP_SHININESS);
+
+    // Perform the same lighting calculation for the 2nd light source (no specular applied).
+    NdotL = max(dot(normal, LIGHT_FRONT_DIR), 0.0);
+    intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+    gl_Position = projection_matrix * position;
+}

resources/shaders/ES/gouraud_light_instanced.fs

@@ -0,0 +1,12 @@
+#version 110
+
+uniform vec4 uniform_color;
+uniform float emission_factor;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+
+void main()
+{
+    gl_FragColor = vec4(vec3(intensity.y) + uniform_color.rgb * (intensity.x + emission_factor), uniform_color.a);
+}

resources/shaders/ES/gouraud_light_instanced.vs

@@ -0,0 +1,50 @@
+#version 110
+
+#define INTENSITY_CORRECTION 0.6
+
+// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+
+#define INTENSITY_AMBIENT    0.3
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat3 normal_matrix;
+
+// vertex attributes
+attribute vec3 v_position;
+attribute vec3 v_normal;
+// instance attributes
+attribute vec3 i_offset;
+attribute vec2 i_scales;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+
+void main()
+{
+    // First transform the normal into camera space and normalize the result.
+    vec3 eye_normal = normalize(normal_matrix * v_normal);
+    
+    // Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+    // Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+    float NdotL = max(dot(eye_normal, LIGHT_TOP_DIR), 0.0);
+
+    intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    vec4 world_position = vec4(v_position * vec3(vec2(1.5 * i_scales.x), 1.5 * i_scales.y) + i_offset - vec3(0.0, 0.0, 0.5 * i_scales.y), 1.0);
+    vec4 eye_position = view_model_matrix * world_position;
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(eye_position.xyz), reflect(-LIGHT_TOP_DIR, eye_normal)), 0.0), LIGHT_TOP_SHININESS);
+
+    // Perform the same lighting calculation for the 2nd light source (no specular applied).
+    NdotL = max(dot(eye_normal, LIGHT_FRONT_DIR), 0.0);
+    intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+    gl_Position = projection_matrix * eye_position;
+}

resources/shaders/ES/imgui.fs

@@ -0,0 +1,13 @@
+#version 110
+
+precision highp float;
+
+uniform sampler2D Texture;
+
+varying vec2 Frag_UV;
+varying vec4 Frag_Color;
+
+void main()
+{
+	gl_FragColor = Frag_Color * texture2D(Texture, Frag_UV.st);
+}

resources/shaders/ES/imgui.vs

@@ -0,0 +1,17 @@
+#version 110
+
+uniform mat4 ProjMtx;
+
+attribute vec2 Position;
+attribute vec2 UV;
+attribute vec4 Color;
+
+varying vec2 Frag_UV;
+varying vec4 Frag_Color;
+
+void main()
+{
+	Frag_UV = UV;
+	Frag_Color = Color;
+    gl_Position = ProjMtx * vec4(Position.xy, 0.0, 1.0);
+}

resources/shaders/ES/mm_contour.fs

@@ -0,0 +1,16 @@
+#version 110
+#extension GL_NV_fragdepth : enable
+
+precision highp float;
+
+const float EPSILON = 0.0001;
+
+uniform vec4 uniform_color;
+
+void main()
+{
+    gl_FragColor = uniform_color;
+    // Values inside depth buffer for fragments of the contour of a selected area are offset
+    // by small epsilon to solve z-fighting between painted triangles and contour lines.
+    gl_FragDepth = gl_FragCoord.z - EPSILON;
+}

resources/shaders/ES/mm_contour.vs

@@ -0,0 +1,11 @@
+#version 110
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+
+attribute vec3 v_position;
+
+void main()
+{
+    gl_Position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
+}

resources/shaders/ES/mm_gouraud.fs

@@ -0,0 +1,66 @@
+#version 110
+#extension GL_OES_standard_derivatives : enable
+
+precision highp float;
+
+#define INTENSITY_CORRECTION 0.6
+
+// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+
+#define INTENSITY_AMBIENT    0.3
+
+const vec3  ZERO    = vec3(0.0, 0.0, 0.0);
+const float EPSILON = 0.0001;
+
+uniform vec4 uniform_color;
+
+uniform bool volume_mirrored;
+
+uniform mat4 view_model_matrix;
+uniform mat3 normal_matrix;
+
+varying vec3 clipping_planes_dots;
+varying vec4 model_pos;
+
+void main()
+{
+    if (any(lessThan(clipping_planes_dots, ZERO)))
+        discard;
+    vec3  color = uniform_color.rgb;
+    float alpha = uniform_color.a;
+
+    vec3 triangle_normal = normalize(cross(dFdx(model_pos.xyz), dFdy(model_pos.xyz)));
+#ifdef FLIP_TRIANGLE_NORMALS
+    triangle_normal = -triangle_normal;
+#endif
+
+    if (volume_mirrored)
+        triangle_normal = -triangle_normal;
+
+    // First transform the normal into camera space and normalize the result.
+    vec3 eye_normal = normalize(normal_matrix * triangle_normal);
+
+    // Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+    // Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+    float NdotL = max(dot(eye_normal, LIGHT_TOP_DIR), 0.0);
+
+    // x = diffuse, y = specular;
+    vec2 intensity = vec2(0.0);
+    intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    vec3 position = (view_model_matrix * model_pos).xyz;
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(position), reflect(-LIGHT_TOP_DIR, eye_normal)), 0.0), LIGHT_TOP_SHININESS);
+
+    // Perform the same lighting calculation for the 2nd light source (no specular applied).
+    NdotL = max(dot(eye_normal, LIGHT_FRONT_DIR), 0.0);
+    intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+    gl_FragColor = vec4(vec3(intensity.y) + color * intensity.x, alpha);
+}

resources/shaders/ES/mm_gouraud.vs

@@ -0,0 +1,28 @@
+#version 110
+
+const vec3 ZERO = vec3(0.0, 0.0, 0.0);
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+
+uniform mat4 volume_world_matrix;
+// Clipping plane, x = min z, y = max z. Used by the FFF and SLA previews to clip with a top / bottom plane.
+uniform vec2 z_range;
+// Clipping plane - general orientation. Used by the SLA gizmo.
+uniform vec4 clipping_plane;
+
+attribute vec3 v_position;
+
+varying vec3 clipping_planes_dots;
+varying vec4 model_pos;
+
+void main()
+{
+    model_pos = vec4(v_position, 1.0);
+    // Point in homogenous coordinates.
+    vec4 world_pos = volume_world_matrix * model_pos;
+
+    gl_Position = projection_matrix * view_model_matrix * model_pos;
+    // Fill in the scalars for fragment shader clipping. Fragments with any of these components lower than zero are discarded.
+    clipping_planes_dots = vec3(dot(world_pos, clipping_plane), world_pos.z - z_range.x, z_range.y - world_pos.z);
+}

resources/shaders/ES/printbed.fs

@@ -0,0 +1,36 @@
+#version 110
+
+precision highp float;
+
+const vec3 back_color_dark  = vec3(0.235, 0.235, 0.235);
+const vec3 back_color_light = vec3(0.365, 0.365, 0.365);
+
+uniform sampler2D texture;
+uniform bool transparent_background;
+uniform bool svg_source;
+
+varying vec2 tex_coord;
+
+vec4 svg_color()
+{
+    // takes foreground from texture
+    vec4 fore_color = texture2D(texture, tex_coord);
+
+    // calculates radial gradient
+    vec3 back_color = vec3(mix(back_color_light, back_color_dark, smoothstep(0.0, 0.5, length(abs(tex_coord.xy) - vec2(0.5)))));
+
+    // blends foreground with background
+    return vec4(mix(back_color, fore_color.rgb, fore_color.a), transparent_background ? fore_color.a : 1.0);
+}
+
+vec4 non_svg_color()
+{
+    // takes foreground from texture
+    vec4 color = texture2D(texture, tex_coord);
+    return vec4(color.rgb, transparent_background ? color.a * 0.25 : color.a);
+}
+
+void main()
+{
+    gl_FragColor = svg_source ? svg_color() : non_svg_color();
+}

resources/shaders/ES/printbed.vs

@@ -0,0 +1,15 @@
+#version 110
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+
+attribute vec3 v_position;
+attribute vec2 v_tex_coord;
+
+varying vec2 tex_coord;
+
+void main()
+{
+	tex_coord = v_tex_coord;
+    gl_Position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
+}

resources/shaders/ES/toolpaths_cog.fs

@@ -0,0 +1,21 @@
+#version 110
+
+precision highp float;
+
+const vec4 BLACK = vec4(vec3(0.1), 1.0);
+const vec4 WHITE = vec4(vec3(1.0), 1.0);
+
+const float emission_factor = 0.25;
+
+uniform vec3 world_center;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+varying vec3 world_position;
+
+void main()
+{
+    vec3 delta = world_position - world_center;
+    vec4 color = delta.x * delta.y * delta.z > 0.0 ? BLACK : WHITE;
+    gl_FragColor = vec4(vec3(intensity.y) + color.rgb * (intensity.x + emission_factor), 1.0);
+}

resources/shaders/ES/toolpaths_cog.vs

@@ -0,0 +1,47 @@
+#version 110
+
+#define INTENSITY_CORRECTION 0.6
+
+// normalized values for (-0.6/1.31, 0.6/1.31, 1./1.31)
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+// normalized values for (1./1.43, 0.2/1.43, 1./1.43)
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+
+#define INTENSITY_AMBIENT    0.3
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat3 normal_matrix;
+
+attribute vec3 v_position;
+attribute vec3 v_normal;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+varying vec3 world_position;
+
+void main()
+{
+    // First transform the normal into camera space and normalize the result.
+    vec3 normal = normalize(normal_matrix * v_normal);
+    
+    // Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+    // Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+    float NdotL = max(dot(normal, LIGHT_TOP_DIR), 0.0);
+
+    intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    vec4 position = view_model_matrix * vec4(v_position, 1.0);
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(position.xyz), reflect(-LIGHT_TOP_DIR, normal)), 0.0), LIGHT_TOP_SHININESS);
+
+    // Perform the same lighting calculation for the 2nd light source (no specular applied).
+    NdotL = max(dot(normal, LIGHT_FRONT_DIR), 0.0);
+    intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+	world_position = v_position;
+    gl_Position = projection_matrix * position;
+}

resources/shaders/ES/variable_layer_height.fs

@@ -0,0 +1,44 @@
+#version 110
+#extension GL_OES_standard_derivatives : enable
+
+precision highp float;
+
+#define M_PI 3.1415926535897932384626433832795
+
+// 2D texture (1D texture split by the rows) of color along the object Z axis.
+uniform sampler2D z_texture;
+// Scaling from the Z texture rows coordinate to the normalized texture row coordinate.
+uniform float z_to_texture_row;
+uniform float z_texture_row_to_normalized;
+uniform float z_cursor;
+uniform float z_cursor_band_width;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+
+varying float object_z;
+
+void main()
+{
+    float object_z_row = z_to_texture_row * object_z;
+    // Index of the row in the texture.
+    float z_texture_row = floor(object_z_row);
+    // Normalized coordinate from 0. to 1.
+    float z_texture_col = object_z_row - z_texture_row;
+    float z_blend = 0.25 * cos(min(M_PI, abs(M_PI * (object_z - z_cursor) * 1.8 / z_cursor_band_width))) + 0.25;
+    // Calculate level of detail from the object Z coordinate.
+    // This makes the slowly sloping surfaces to be shown with high detail (with stripes),
+    // and the vertical surfaces to be shown with low detail (no stripes)
+    float z_in_cells = object_z_row * 190.;
+    // Gradient of Z projected on the screen.
+    float dx_vtc = dFdx(z_in_cells);
+    float dy_vtc = dFdy(z_in_cells);
+    float lod = clamp(0.5 * log2(max(dx_vtc * dx_vtc, dy_vtc * dy_vtc)), 0., 1.);
+    // Sample the Z texture. Texture coordinates are normalized to <0, 1>.
+    vec4 color = vec4(0.25, 0.25, 0.25, 1.0);
+    if (z_texture_row >= 0.0)
+        color = mix(texture2D(z_texture, vec2(z_texture_col, z_texture_row_to_normalized * (z_texture_row + 0.5    )), -10000.),
+                    texture2D(z_texture, vec2(z_texture_col, z_texture_row_to_normalized * (z_texture_row * 2. + 1.)),  10000.), lod);            
+    // Mix the final color.
+    gl_FragColor = vec4(vec3(intensity.y), 1.0) +  intensity.x * mix(color, vec4(1.0, 1.0, 0.0, 1.0), z_blend);
+}

resources/shaders/ES/variable_layer_height.vs

@@ -0,0 +1,60 @@
+#version 110
+
+#define INTENSITY_CORRECTION 0.6
+
+const vec3 LIGHT_TOP_DIR = vec3(-0.4574957, 0.4574957, 0.7624929);
+#define LIGHT_TOP_DIFFUSE    (0.8 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SPECULAR   (0.125 * INTENSITY_CORRECTION)
+#define LIGHT_TOP_SHININESS  20.0
+
+const vec3 LIGHT_FRONT_DIR = vec3(0.6985074, 0.1397015, 0.6985074);
+#define LIGHT_FRONT_DIFFUSE  (0.3 * INTENSITY_CORRECTION)
+//#define LIGHT_FRONT_SPECULAR (0.0 * INTENSITY_CORRECTION)
+//#define LIGHT_FRONT_SHININESS 5.0
+
+#define INTENSITY_AMBIENT    0.3
+
+uniform mat4 view_model_matrix;
+uniform mat4 projection_matrix;
+uniform mat3 normal_matrix;
+uniform mat4 volume_world_matrix;
+uniform float object_max_z;
+
+attribute vec3 v_position;
+attribute vec3 v_normal;
+attribute vec2 v_tex_coord;
+
+// x = tainted, y = specular;
+varying vec2 intensity;
+
+varying float object_z;
+
+void main()
+{
+	// =====================================================
+	// NOTE:
+	// when object_max_z > 0.0  we are rendering the overlay
+	// when object_max_z == 0.0 we are rendering the volumes
+	// =====================================================
+
+    // First transform the normal into camera space and normalize the result.
+    vec3 normal = (object_max_z > 0.0) ? vec3(0.0, 0.0, 1.0) : normalize(normal_matrix * v_normal);
+    
+    // Compute the cos of the angle between the normal and lights direction. The light is directional so the direction is constant for every vertex.
+    // Since these two are normalized the cosine is the dot product. We also need to clamp the result to the [0,1] range.
+    float NdotL = max(dot(normal, LIGHT_TOP_DIR), 0.0);
+
+    intensity.x = INTENSITY_AMBIENT + NdotL * LIGHT_TOP_DIFFUSE;
+    vec4 position = view_model_matrix * vec4(v_position, 1.0);
+    intensity.y = LIGHT_TOP_SPECULAR * pow(max(dot(-normalize(position.xyz), reflect(-LIGHT_TOP_DIR, normal)), 0.0), LIGHT_TOP_SHININESS);
+
+    // Perform the same lighting calculation for the 2nd light source (no specular)
+    NdotL = max(dot(normal, LIGHT_FRONT_DIR), 0.0);
+    
+    intensity.x += NdotL * LIGHT_FRONT_DIFFUSE;
+
+    // Scaled to widths of the Z texture.
+    object_z = (object_max_z > 0.0) ? object_max_z * v_tex_coord.y : (volume_world_matrix * vec4(v_position, 1.0)).z;
+        
+    gl_Position = projection_matrix * position;
+}

src/libslic3r/Technologies.hpp

@@ -55,8 +55,10 @@
 #define ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL (1 && ENABLE_2_5_0_ALPHA1)
 // Enable removal of legacy OpenGL calls
 #define ENABLE_LEGACY_OPENGL_REMOVAL (1 && ENABLE_2_5_0_ALPHA1)
+// Enable OpenGL ES
+#define ENABLE_OPENGL_ES (1 && ENABLE_LEGACY_OPENGL_REMOVAL)
 // Enable OpenGL core profile context (tested against Mesa 20.1.8 on Windows)
-#define ENABLE_GL_CORE_PROFILE (1 && ENABLE_LEGACY_OPENGL_REMOVAL)
+#define ENABLE_GL_CORE_PROFILE (1 && ENABLE_LEGACY_OPENGL_REMOVAL && !ENABLE_OPENGL_ES)
 // Shows an imgui dialog with GLModel statistics data
 #define ENABLE_GLMODEL_STATISTICS (0 && ENABLE_LEGACY_OPENGL_REMOVAL)
 // Enable show non-manifold edges

src/slic3r/GUI/3DScene.cpp

@@ -903,13 +903,25 @@ void GLVolumeCollection::load_object_auxiliary(
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
 #if ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
+#if ENABLE_OPENGL_ES
+int GLVolumeCollection::load_wipe_tower_preview(
+    float pos_x, float pos_y, float width, float depth, float height,
+    float rotation_angle, bool size_unknown, float brim_width, TriangleMesh* out_mesh)
+#else
 int GLVolumeCollection::load_wipe_tower_preview(
     float pos_x, float pos_y, float width, float depth, float height,
     float rotation_angle, bool size_unknown, float brim_width)
+#endif // ENABLE_OPENGL_ES
+#else
+#if ENABLE_OPENGL_ES
+int GLVolumeCollection::load_wipe_tower_preview(
+    int obj_idx, float pos_x, float pos_y, float width, float depth, float height,
+    float rotation_angle, bool size_unknown, float brim_width, TriangleMesh* out_mesh)
 #else
 int GLVolumeCollection::load_wipe_tower_preview(
     int obj_idx, float pos_x, float pos_y, float width, float depth, float height,
     float rotation_angle, bool size_unknown, float brim_width)
+#endif // ENABLE_OPENGL_ES
 #endif // ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
 #else
 #if ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
@@ -979,6 +991,10 @@ int GLVolumeCollection::load_wipe_tower_preview(
     volumes.emplace_back(new GLVolume(color));
     GLVolume& v = *volumes.back();
 #if ENABLE_LEGACY_OPENGL_REMOVAL
+#if ENABLE_OPENGL_ES
+    if (out_mesh != nullptr)
+        *out_mesh = mesh;
+#endif // ENABLE_OPENGL_ES
     v.model.init_from(mesh);
     v.model.set_color(color);
 #else

src/slic3r/GUI/3DScene.hpp

@@ -638,11 +638,21 @@ public:
         size_t                          timestamp);
 
 #if ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
+#if ENABLE_OPENGL_ES
+    int load_wipe_tower_preview(
+        float pos_x, float pos_y, float width, float depth, float height, float rotation_angle, bool size_unknown, float brim_width, TriangleMesh* out_mesh = nullptr);
+#else
     int load_wipe_tower_preview(
         float pos_x, float pos_y, float width, float depth, float height, float rotation_angle, bool size_unknown, float brim_width);
+#endif // ENABLE_OPENGL_ES
+#else
+#if ENABLE_OPENGL_ES
+    int load_wipe_tower_preview(
+        int obj_idx, float pos_x, float pos_y, float width, float depth, float height, float rotation_angle, bool size_unknown, float brim_width, TriangleMesh* out_mesh = nullptr);
 #else
     int load_wipe_tower_preview(
         int obj_idx, float pos_x, float pos_y, float width, float depth, float height, float rotation_angle, bool size_unknown, float brim_width);
+#endif // ENABLE_OPENGL_ES
 #endif // ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
 #else
     std::vector<int> load_object(

src/slic3r/GUI/GCodeViewer.cpp

@@ -1221,9 +1221,16 @@ void GCodeViewer::export_toolpaths_to_obj(const char* filename) const
     // get vertices/normals data from vertex buffers on gpu
     for (size_t i = 0; i < t_buffer.vertices.vbos.size(); ++i) {
         const size_t floats_count = t_buffer.vertices.sizes[i] / sizeof(float);
-        VertexBuffer vertices(floats_count);
         glsafe(::glBindBuffer(GL_ARRAY_BUFFER, t_buffer.vertices.vbos[i]));
+#if ENABLE_OPENGL_ES
+        const VertexBuffer vertices = *static_cast<VertexBuffer*>(::glMapBufferRange(GL_ARRAY_BUFFER, 0,
+            static_cast<GLsizeiptr>(t_buffer.vertices.sizes[i]), GL_MAP_READ_BIT));
+        glcheck();
+        glsafe(::glUnmapBuffer(GL_ARRAY_BUFFER));
+#else
+        VertexBuffer vertices(floats_count);
         glsafe(::glGetBufferSubData(GL_ARRAY_BUFFER, 0, static_cast<GLsizeiptr>(t_buffer.vertices.sizes[i]), static_cast<void*>(vertices.data())));
+#endif // ENABLE_OPENGL_ES
         glsafe(::glBindBuffer(GL_ARRAY_BUFFER, 0));
         const size_t vertices_count = floats_count / floats_per_vertex;
         for (size_t j = 0; j < vertices_count; ++j) {
@@ -1271,9 +1278,17 @@ void GCodeViewer::export_toolpaths_to_obj(const char* filename) const
             // get indices data from index buffer on gpu
             glsafe(::glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ibuffer.ibo));
             for (size_t j = 0; j < render_path.sizes.size(); ++j) {
+#if ENABLE_OPENGL_ES
+                const IndexBuffer indices = *static_cast<IndexBuffer*>(::glMapBufferRange(GL_ELEMENT_ARRAY_BUFFER,
+                    static_cast<GLintptr>(render_path.offsets[j]), static_cast<GLsizeiptr>(render_path.sizes[j] * sizeof(IBufferType)),
+                    GL_MAP_READ_BIT));
+                glcheck();
+                glsafe(::glUnmapBuffer(GL_ELEMENT_ARRAY_BUFFER));
+#else
                 IndexBuffer indices(render_path.sizes[j]);
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>(render_path.offsets[j]),
                     static_cast<GLsizeiptr>(render_path.sizes[j] * sizeof(IBufferType)), static_cast<void*>(indices.data())));
+#endif // ENABLE_OPENGL_ES
 
                 const size_t triangles_count = render_path.sizes[j] / 3;
                 for (size_t k = 0; k < triangles_count; ++k) {
@@ -2682,14 +2697,30 @@ void GCodeViewer::refresh_render_paths(bool keep_sequential_current_first, bool
 
                         // gets the vertex index from the index buffer on gpu
                         const IBuffer& i_buffer = buffer.indices[sub_path.first.b_id];
-                        IBufferType index = 0;
                         glsafe(::glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, i_buffer.ibo));
+#if ENABLE_OPENGL_ES
+                        IBufferType index = *static_cast<IBufferType*>(::glMapBufferRange(GL_ELEMENT_ARRAY_BUFFER,
+                            static_cast<GLintptr>(offset * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)),
+                            GL_MAP_READ_BIT));
+                        glcheck();
+                        glsafe(::glUnmapBuffer(GL_ELEMENT_ARRAY_BUFFER));
+#else
+                        IBufferType index = 0;
                         glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>(offset * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&index)));
+#endif // ENABLE_OPENGL_ES
                         glsafe(::glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0));
 
                         // gets the position from the vertices buffer on gpu
                         glsafe(::glBindBuffer(GL_ARRAY_BUFFER, i_buffer.vbo));
-                        glsafe(::glGetBufferSubData(GL_ARRAY_BUFFER, static_cast<GLintptr>(index * buffer.vertices.vertex_size_bytes()), static_cast<GLsizeiptr>(3 * sizeof(float)), static_cast<void*>(sequential_view->current_position.data())));
+#if ENABLE_OPENGL_ES
+                        sequential_view->current_position = *static_cast<Vec3f*>(::glMapBufferRange(GL_ARRAY_BUFFER,
+                            static_cast<GLintptr>(index * buffer.vertices.vertex_size_bytes()),
+                            static_cast<GLsizeiptr>(buffer.vertices.position_size_bytes()), GL_MAP_READ_BIT));
+                        glcheck();
+                        glsafe(::glUnmapBuffer(GL_ARRAY_BUFFER));
+#else
+                        glsafe(::glGetBufferSubData(GL_ARRAY_BUFFER, static_cast<GLintptr>(index* buffer.vertices.vertex_size_bytes()), static_cast<GLsizeiptr>(3 * sizeof(float)), static_cast<void*>(sequential_view->current_position.data())));
+#endif // ENABLE_OPENGL_ES
                         glsafe(::glBindBuffer(GL_ARRAY_BUFFER, 0));
 
                         sequential_view->current_offset = Vec3f::Zero();
@@ -2896,10 +2927,22 @@ void GCodeViewer::refresh_render_paths(bool keep_sequential_current_first, bool
                 // extract indices from index buffer
                 std::array<IBufferType, 6> indices{ 0, 0, 0, 0, 0, 0 };
                 glsafe(::glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, i_buffer.ibo));
+#if ENABLE_OPENGL_ES
+                IBufferType* index_ptr = static_cast<IBufferType*>(::glMapBufferRange(GL_ELEMENT_ARRAY_BUFFER,
+                    static_cast<GLintptr>(offset * sizeof(IBufferType)), static_cast<GLsizeiptr>(14 * sizeof(IBufferType)),
+                    GL_MAP_READ_BIT));
+                glcheck();
+                indices[0] = *(index_ptr + 0);
+                indices[1] = *(index_ptr + 7);
+                indices[2] = *(index_ptr + 1);
+                indices[4] = *(index_ptr + 13);
+                glsafe(::glUnmapBuffer(GL_ELEMENT_ARRAY_BUFFER));
+#else
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 0) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[0])));
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 7) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[1])));
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 1) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[2])));
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 13) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[4])));
+#endif // ENABLE_OPENGL_ES
                 glsafe(::glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0));
                 indices[3] = indices[0];
                 indices[5] = indices[1];
@@ -2944,10 +2987,22 @@ void GCodeViewer::refresh_render_paths(bool keep_sequential_current_first, bool
                 // extract indices from index buffer
                 std::array<IBufferType, 6> indices{ 0, 0, 0, 0, 0, 0 };
                 glsafe(::glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, i_buffer.ibo));
+#if ENABLE_OPENGL_ES
+                IBufferType* index_ptr = static_cast<IBufferType*>(::glMapBufferRange(GL_ELEMENT_ARRAY_BUFFER,
+                    static_cast<GLintptr>(offset * sizeof(IBufferType)), static_cast<GLsizeiptr>(17 * sizeof(IBufferType)),
+                    GL_MAP_READ_BIT));
+                glcheck();
+                indices[0] = *(index_ptr + 2);
+                indices[1] = *(index_ptr + 4);
+                indices[2] = *(index_ptr + 10);
+                indices[5] = *(index_ptr + 16);
+                glsafe(::glUnmapBuffer(GL_ELEMENT_ARRAY_BUFFER));
+#else
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 2) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[0])));
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 4) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[1])));
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 10) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[2])));
                 glsafe(::glGetBufferSubData(GL_ELEMENT_ARRAY_BUFFER, static_cast<GLintptr>((offset + 16) * sizeof(IBufferType)), static_cast<GLsizeiptr>(sizeof(IBufferType)), static_cast<void*>(&indices[5])));
+#endif // ENABLE_OPENGL_ES
                 glsafe(::glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0));
                 indices[3] = indices[0];
                 indices[4] = indices[2];
@@ -3029,7 +3084,14 @@ void GCodeViewer::render_toolpaths()
             shader.set_uniform("gap_size", 0.0f);
 #endif // ENABLE_GL_CORE_PROFILE
 
+#if ENABLE_OPENGL_ES
+            for (size_t i = 0; i < path.sizes.size(); ++i) {
+                glsafe(::glDrawElements(GL_LINES, (GLsizei)path.sizes[i], GL_UNSIGNED_SHORT, (const void*)path.offsets[i]));
+            }
+#else
             glsafe(::glMultiDrawElements(GL_LINES, (const GLsizei*)path.sizes.data(), GL_UNSIGNED_SHORT, (const void* const*)path.offsets.data(), (GLsizei)path.sizes.size()));
+#endif // ENABLE_OPENGL_ES
+
 #if ENABLE_GCODE_VIEWER_STATISTICS
             ++m_statistics.gl_multi_lines_calls_count;
 #endif // ENABLE_GCODE_VIEWER_STATISTICS
@@ -3047,7 +3109,15 @@ void GCodeViewer::render_toolpaths()
             assert(! path.sizes.empty());
             assert(! path.offsets.empty());
             shader.set_uniform(uniform_color, path.color);
+
+#if ENABLE_OPENGL_ES
+            for (size_t i = 0; i < path.sizes.size(); ++i) {
+                glsafe(::glDrawElements(GL_TRIANGLES, (GLsizei)path.sizes[i], GL_UNSIGNED_SHORT, (const void*)path.offsets[i]));
+            }
+#else
             glsafe(::glMultiDrawElements(GL_TRIANGLES, (const GLsizei*)path.sizes.data(), GL_UNSIGNED_SHORT, (const void* const*)path.offsets.data(), (GLsizei)path.sizes.size()));
+#endif // ENABLE_OPENGL_ES
+
 #if ENABLE_GCODE_VIEWER_STATISTICS
             ++m_statistics.gl_multi_triangles_calls_count;
 #endif // ENABLE_GCODE_VIEWER_STATISTICS

src/slic3r/GUI/GLCanvas3D.cpp

@@ -1216,7 +1216,11 @@ bool GLCanvas3D::init()
         return false;
 
     glsafe(::glClearColor(1.0f, 1.0f, 1.0f, 1.0f));
+#if ENABLE_OPENGL_ES
+    glsafe(::glClearDepthf(1.0f));
+#else
     glsafe(::glClearDepth(1.0f));
+#endif // ENABLE_OPENGL_ES
 
     glsafe(::glDepthFunc(GL_LESS));
 
@@ -2055,6 +2059,9 @@ void GLCanvas3D::reload_scene(bool refresh_immediately, bool force_full_scene_re
             if (volume->is_wipe_tower) {
                 // There is only one wipe tower.
                 assert(volume_idx_wipe_tower_old == -1);
+#if ENABLE_OPENGL_ES
+                m_wipe_tower_mesh.clear();
+#endif // ENABLE_OPENGL_ES
                 volume_idx_wipe_tower_old = (int)volume_id;
             }
             if (!m_reload_delayed) {
@@ -2294,13 +2301,25 @@ void GLCanvas3D::reload_scene(bool refresh_immediately, bool force_full_scene_re
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
 #if ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
+#if ENABLE_OPENGL_ES
+            int volume_idx_wipe_tower_new = m_volumes.load_wipe_tower_preview(
+                x, y, w, depth, (float)height, a, !print->is_step_done(psWipeTower),
+                brim_width, &m_wipe_tower_mesh);
+#else
             int volume_idx_wipe_tower_new = m_volumes.load_wipe_tower_preview(
                 x, y, w, depth, (float)height, a, !print->is_step_done(psWipeTower),
                 brim_width);
+#endif // ENABLE_OPENGL_ES
+#else
+#if ENABLE_OPENGL_ES
+            int volume_idx_wipe_tower_new = m_volumes.load_wipe_tower_preview(
+                1000, x, y, w, depth, (float)height, a, !print->is_step_done(psWipeTower),
+                brim_width, &m_wipe_tower_mesh);
 #else
             int volume_idx_wipe_tower_new = m_volumes.load_wipe_tower_preview(
                 1000, x, y, w, depth, (float)height, a, !print->is_step_done(psWipeTower),
                 brim_width);
+#endif // ENABLE_OPENGL_ES
 #endif // ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
 #else
 #if ENABLE_WIPETOWER_OBJECTID_1000_REMOVAL
@@ -6444,6 +6463,43 @@ Vec3d GLCanvas3D::_mouse_to_3d(const Point& mouse_pos, float* z)
     if (m_canvas == nullptr)
         return Vec3d(DBL_MAX, DBL_MAX, DBL_MAX);
 
+#if ENABLE_OPENGL_ES
+    if (z == nullptr) {
+        const Camera& camera = wxGetApp().plater()->get_camera();
+        std::vector<Vec3d> hits;
+        for (GLVolume* v : m_volumes.volumes) {
+            if (v->is_active) {
+                const MeshRaycaster raycaster(v->is_wipe_tower ? m_wipe_tower_mesh : m_model->objects[v->object_idx()]->volumes[v->volume_idx()]->mesh());
+                Vec3f hit_position;
+                Vec3f hit_normal;
+                const Transform3d trafo = v->world_matrix();
+                if (raycaster.unproject_on_mesh(mouse_pos.cast<double>(), trafo, camera, hit_position, hit_normal))
+                    hits.emplace_back(trafo * hit_position.cast<double>());
+            }
+        }
+        if (hits.empty())
+            return _mouse_to_bed_3d(mouse_pos);
+        else {
+            const Vec3d camera_position = camera.get_position();
+            std::sort(hits.begin(), hits.end(), [&camera_position](const Vec3d& h1, const Vec3d& h2) {
+                return (h1 - camera_position).squaredNorm() < (h2 - camera_position).squaredNorm();
+                });
+            return hits.front();
+        }
+    }
+    else {
+        const Camera& camera = wxGetApp().plater()->get_camera();
+        const Matrix4d modelview = camera.get_view_matrix().matrix();
+        const Matrix4d projection = camera.get_projection_matrix().matrix();
+        const Vec4i viewport(camera.get_viewport().data());
+
+        const int y = viewport[3] - mouse_pos.y();
+
+        Vec3d out;
+        igl::unproject(Vec3d(mouse_pos.x(), y, *z), modelview, projection, viewport, out);
+        return out;
+    }
+#else
     const Camera& camera = wxGetApp().plater()->get_camera();
     const Matrix4d modelview  = camera.get_view_matrix().matrix();
     const Matrix4d projection = camera.get_projection_matrix().matrix();
@@ -6459,6 +6515,7 @@ Vec3d GLCanvas3D::_mouse_to_3d(const Point& mouse_pos, float* z)
     Vec3d out;
     igl::unproject(Vec3d(mouse_pos.x(), y, mouse_z), modelview, projection, viewport, out);
     return out;
+#endif // ENABLE_OPENGL_ES
 }
 
 Vec3d GLCanvas3D::_mouse_to_bed_3d(const Point& mouse_pos)

src/slic3r/GUI/GLCanvas3D.hpp

@@ -498,6 +498,9 @@ private:
     bool m_event_handlers_bound{ false };
 
     GLVolumeCollection m_volumes;
+#if ENABLE_OPENGL_ES
+    TriangleMesh m_wipe_tower_mesh;
+#endif // ENABLE_OPENGL_ES
     GCodeViewer m_gcode_viewer;
 
     RenderTimer m_render_timer;

src/slic3r/GUI/GLSelectionRectangle.cpp

@@ -128,11 +128,11 @@ namespace GUI {
         glsafe(::glScaled(gui_scale, gui_scale, 1.0));
 #endif // !ENABLE_LEGACY_OPENGL_REMOVAL
 
-#if !ENABLE_GL_CORE_PROFILE
+#if !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
         glsafe(::glPushAttrib(GL_ENABLE_BIT));
         glsafe(::glLineStipple(4, 0xAAAA));
         glsafe(::glEnable(GL_LINE_STIPPLE));
-#endif // !ENABLE_GL_CORE_PROFILE
+#endif // !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
 #if ENABLE_GL_CORE_PROFILE
@@ -225,9 +225,9 @@ namespace GUI {
         glsafe(::glEnd());
 #endif // ENABLE_LEGACY_OPENGL_REMOVAL
 
-#if !ENABLE_GL_CORE_PROFILE
+#if !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
         glsafe(::glPopAttrib());
-#endif // !ENABLE_GL_CORE_PROFILE
+#endif // !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
 
 #if !ENABLE_LEGACY_OPENGL_REMOVAL
         glsafe(::glPopMatrix());

src/slic3r/GUI/GLShadersManager.cpp

@@ -34,7 +34,11 @@ std::pair<bool, std::string> GLShadersManager::init()
     bool valid = true;
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
+#if ENABLE_OPENGL_ES
+    const std::string prefix = "ES/";
+#else
     const std::string prefix = GUI::wxGetApp().is_gl_version_greater_or_equal_to(3, 1) ? "140/" : "110/";
+#endif // ENABLE_OPENGL_ES
     // imgui shader
     valid &= append_shader("imgui", { prefix + "imgui.vs", prefix + "imgui.fs" });
     // basic shader, used to render all what was previously rendered using the immediate mode

src/slic3r/GUI/GLTexture.cpp

@@ -334,10 +334,10 @@ void GLTexture::render_sub_texture(unsigned int tex_id, float left, float right,
     glsafe(::glEnable(GL_BLEND));
     glsafe(::glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA));
 
-#if !ENABLE_GL_CORE_PROFILE
+#if !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
     glsafe(::glEnable(GL_TEXTURE_2D));
     glsafe(::glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE));
-#endif // !ENABLE_GL_CORE_PROFILE
+#endif // !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
 
     glsafe(::glBindTexture(GL_TEXTURE_2D, (GLuint)tex_id));
 
@@ -381,9 +381,9 @@ void GLTexture::render_sub_texture(unsigned int tex_id, float left, float right,
 
     glsafe(::glBindTexture(GL_TEXTURE_2D, 0));
 
-#if !ENABLE_GL_CORE_PROFILE
+#if !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
     glsafe(::glDisable(GL_TEXTURE_2D));
-#endif // !ENABLE_GL_CORE_PROFILE
+#endif // !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
     glsafe(::glDisable(GL_BLEND));
 }
 

src/slic3r/GUI/Gizmos/GLGizmoPainterBase.cpp

@@ -210,11 +210,11 @@ void GLGizmoPainterBase::render_cursor_circle()
     glsafe(::glScaled(gui_scale, gui_scale, 1.0));
 #endif // !ENABLE_LEGACY_OPENGL_REMOVAL
 
-#if !ENABLE_GL_CORE_PROFILE
+#if !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
     glsafe(::glPushAttrib(GL_ENABLE_BIT));
     glsafe(::glLineStipple(4, 0xAAAA));
     glsafe(::glEnable(GL_LINE_STIPPLE));
-#endif // !ENABLE_GL_CORE_PROFILE
+#endif // !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
     if (!m_circle.is_initialized() || !m_old_center.isApprox(center) || std::abs(m_old_cursor_radius - radius) > EPSILON) {
@@ -292,9 +292,9 @@ void GLGizmoPainterBase::render_cursor_circle()
     glsafe(::glEnd());
 #endif // ENABLE_LEGACY_OPENGL_REMOVAL
 
-#if !ENABLE_GL_CORE_PROFILE
+#if !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
     glsafe(::glPopAttrib());
-#endif // !ENABLE_GL_CORE_PROFILE
+#endif // !ENABLE_GL_CORE_PROFILE && !ENABLE_OPENGL_ES
 #if !ENABLE_LEGACY_OPENGL_REMOVAL
     glsafe(::glPopMatrix());
 #endif // !ENABLE_LEGACY_OPENGL_REMOVAL

src/slic3r/GUI/Gizmos/GLGizmoSimplify.cpp

@@ -742,11 +742,11 @@ void GLGizmoSimplify::on_render()
         glsafe(::glMultMatrixd(trafo_matrix.data()));
 #endif // !ENABLE_LEGACY_OPENGL_REMOVAL
         auto* gouraud_shader = wxGetApp().get_shader("gouraud_light");
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         bool depth_test_enabled = ::glIsEnabled(GL_DEPTH_TEST);
 #else
         glsafe(::glPushAttrib(GL_DEPTH_TEST));
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         glsafe(::glEnable(GL_DEPTH_TEST));
         gouraud_shader->start_using();
 #if ENABLE_LEGACY_OPENGL_REMOVAL
@@ -779,12 +779,12 @@ void GLGizmoSimplify::on_render()
 #endif // ENABLE_LEGACY_OPENGL_REMOVAL
             contour_shader->stop_using();
         }
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         if (depth_test_enabled)
             glsafe(::glEnable(GL_DEPTH_TEST));
 #else
         glsafe(::glPopAttrib());
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 #if !ENABLE_LEGACY_OPENGL_REMOVAL
         glsafe(::glPopMatrix());
 #endif // !ENABLE_LEGACY_OPENGL_REMOVAL

src/slic3r/GUI/Gizmos/GLGizmosCommon.cpp

@@ -222,23 +222,23 @@ void InstancesHider::render_cut() const
             glsafe(::glColor4fv(color.data()));
         }
 #endif // !ENABLE_LEGACY_OPENGL_REMOVAL
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         bool depth_test_enabled = ::glIsEnabled(GL_DEPTH_TEST);
 #else
         glsafe(::glPushAttrib(GL_DEPTH_TEST));
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         glsafe(::glDisable(GL_DEPTH_TEST));
 #if ENABLE_LEGACY_OPENGL_REMOVAL
         clipper->render_cut(mv->is_model_part() ? ColorRGBA(0.8f, 0.3f, 0.0f, 1.0f) : color_from_model_volume(*mv));
 #else
         clipper->render_cut();
 #endif // ENABLE_LEGACY_OPENGL_REMOVAL
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         if (depth_test_enabled)
             glsafe(::glEnable(GL_DEPTH_TEST));
 #else
         glsafe(::glPopAttrib());
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 #if !ENABLE_LEGACY_OPENGL_REMOVAL
         glsafe(::glPopMatrix());
 #endif // !ENABLE_LEGACY_OPENGL_REMOVAL

src/slic3r/GUI/ImGuiWrapper.cpp

@@ -1471,7 +1471,7 @@ void ImGuiWrapper::render_draw_data(ImDrawData *draw_data)
     draw_data->ScaleClipRects(io.DisplayFramebufferScale);
 #endif // ENABLE_LEGACY_OPENGL_REMOVAL
 
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
     // Backup GL state
     GLenum last_active_texture;       glsafe(::glGetIntegerv(GL_ACTIVE_TEXTURE, (GLint*)&last_active_texture));
     GLuint last_program;              glsafe(::glGetIntegerv(GL_CURRENT_PROGRAM, (GLint*)&last_program));
@@ -1526,7 +1526,7 @@ void ImGuiWrapper::render_draw_data(ImDrawData *draw_data)
     glsafe(::glEnable(GL_TEXTURE_2D));
     glsafe(::glPolygonMode(GL_FRONT_AND_BACK, GL_FILL));
     glsafe(::glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE));
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
     // Setup viewport, orthographic projection matrix
@@ -1665,7 +1665,7 @@ void ImGuiWrapper::render_draw_data(ImDrawData *draw_data)
 #endif // ENABLE_LEGACY_OPENGL_REMOVAL
     }
 
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
     // Restore modified GL state
     glsafe(::glBindTexture(GL_TEXTURE_2D, last_texture));
     glsafe(::glActiveTexture(last_active_texture));
@@ -1698,7 +1698,7 @@ void ImGuiWrapper::render_draw_data(ImDrawData *draw_data)
     glsafe(::glPolygonMode(GL_BACK, (GLenum)last_polygon_mode[1])));
     glsafe(::glViewport(last_viewport[0], last_viewport[1], (GLsizei)last_viewport[2], (GLsizei)last_viewport[3]));
     glsafe(::glScissor(last_scissor_box[0], last_scissor_box[1], (GLsizei)last_scissor_box[2], (GLsizei)last_scissor_box[3]));
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 
 #if ENABLE_LEGACY_OPENGL_REMOVAL
     shader->stop_using();

src/slic3r/GUI/OpenGLManager.cpp

@@ -78,7 +78,7 @@ bool OpenGLManager::GLInfo::is_mesa() const
     return boost::icontains(m_version, "mesa");
 }
 #endif // _WIN32
-#endif // ENABLE_OPENGL_ES
+#endif // ENABLE_GL_CORE_PROFILE
 
 int OpenGLManager::GLInfo::get_max_tex_size() const
 {
@@ -136,8 +136,16 @@ static bool version_greater_or_equal_to(const std::string& version, unsigned int
     if (tokens.empty())
         return false;
 
+#if ENABLE_OPENGL_ES
+    const std::string version_container = (tokens.size() > 1 && boost::istarts_with(tokens[1], "ES")) ? tokens[2] : tokens[0];
+#endif // ENABLE_OPENGL_ES
+
     std::vector<std::string> numbers;
+#if ENABLE_OPENGL_ES
+    boost::split(numbers, version_container, boost::is_any_of("."), boost::token_compress_on);
+#else
     boost::split(numbers, tokens[0], boost::is_any_of("."), boost::token_compress_on);
+#endif // ENABLE_OPENGL_ES
 
     unsigned int gl_major = 0;
     unsigned int gl_minor = 0;
@@ -192,6 +200,8 @@ std::string OpenGLManager::GLInfo::to_string(bool for_github) const
     out << b_start << "GL version:   " << b_end << m_version << line_end;
 #if ENABLE_GL_CORE_PROFILE
     out << b_start << "Profile:      " << b_end << (is_core_profile() ? "Core" : "Compatibility") << line_end;
+#else
+    out << b_start << "Profile:      " << b_end << "Compatibility" << line_end;
 #endif // ENABLE_GL_CORE_PROFILE
     out << b_start << "Vendor:       " << b_end << m_vendor << line_end;
     out << b_start << "Renderer:     " << b_end << m_renderer << line_end;
@@ -268,9 +278,9 @@ OpenGLManager::~OpenGLManager()
 bool OpenGLManager::init_gl()
 {
     if (!m_gl_initialized) {
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         glewExperimental = true;
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
         GLenum err = glewInit();
         if (err != GLEW_OK) {
             BOOST_LOG_TRIVIAL(error) << "Unable to init glew library: " << glewGetErrorString(err);
@@ -279,7 +289,7 @@ bool OpenGLManager::init_gl()
 
 #if ENABLE_GL_CORE_PROFILE
         do {
-            // glewInit() generates an OpenGL GL_INVALID_ENUM error
+            // glewInit() generates an OpenGL GL_INVALID_ENUM error when using core profile
             err = ::glGetError();
         } while (err != GL_NO_ERROR);
 #endif // ENABLE_GL_CORE_PROFILE
@@ -304,21 +314,26 @@ bool OpenGLManager::init_gl()
         else
             s_framebuffers_type = EFramebufferType::Unknown;
 
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_OPENGL_ES
+        bool valid_version = s_gl_info.is_version_greater_or_equal_to(2, 0);
+#elif ENABLE_GL_CORE_PROFILE
         bool valid_version = s_gl_info.is_core_profile() ? s_gl_info.is_version_greater_or_equal_to(3, 3) : s_gl_info.is_version_greater_or_equal_to(2, 0);
 #else
         bool valid_version = s_gl_info.is_version_greater_or_equal_to(2, 0);
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_OPENGL_ES
         if (!valid_version) {
             // Complain about the OpenGL version.
             wxString message = from_u8((boost::format(
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_OPENGL_ES
+                _utf8(L("PrusaSlicer requires OpenGL ES 2.0 capable graphics driver to run correctly, \n"
+                    "while OpenGL version %s, render %s, vendor %s was detected."))) % s_gl_info.get_version() % s_gl_info.get_renderer() % s_gl_info.get_vendor()).str());
+#elif ENABLE_GL_CORE_PROFILE
                 _utf8(L("PrusaSlicer requires OpenGL %s capable graphics driver to run correctly, \n"
                     "while OpenGL version %s, render %s, vendor %s was detected."))) % (s_gl_info.is_core_profile() ? "3.3" : "2.0") % s_gl_info.get_version() % s_gl_info.get_renderer() % s_gl_info.get_vendor()).str());
 #else
                 _utf8(L("PrusaSlicer requires OpenGL 2.0 capable graphics driver to run correctly, \n"
                     "while OpenGL version %s, render %s, vendor %s was detected."))) % s_gl_info.get_version() % s_gl_info.get_renderer() % s_gl_info.get_vendor()).str());
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_OPENGL_ES
             message += "\n";
         	message += _L("You may need to update your graphics card driver.");
 #ifdef _WIN32
@@ -345,13 +360,17 @@ bool OpenGLManager::init_gl()
 wxGLContext* OpenGLManager::init_glcontext(wxGLCanvas& canvas)
 {
     if (m_context == nullptr) {
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_OPENGL_ES
+        wxGLContextAttrs attrs;
+        attrs.ES2().MajorVersion(2).EndList();
+        m_context = new wxGLContext(&canvas, nullptr, &attrs);
+#elif ENABLE_GL_CORE_PROFILE
         wxGLContextAttrs attrs;
         attrs.CoreProfile().ForwardCompatible().OGLVersion(3, 3).EndList();
         m_context = new wxGLContext(&canvas, nullptr, &attrs);
 #else
         m_context = new wxGLContext(&canvas);
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_OPENGL_ES
 
 #ifdef __APPLE__ 
         // Part of hack to remove crash when closing the application on OSX 10.9.5 when building against newer wxWidgets
@@ -365,7 +384,7 @@ wxGLContext* OpenGLManager::init_glcontext(wxGLCanvas& canvas)
 
 wxGLCanvas* OpenGLManager::create_wxglcanvas(wxWindow& parent)
 {
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
     wxGLAttributes attribList;
     attribList.PlatformDefaults().RGBA().DoubleBuffer().MinRGBA(8, 8, 8, 8).Depth(24).SampleBuffers(1).Samplers(4).EndList();
 #else
@@ -384,7 +403,7 @@ wxGLCanvas* OpenGLManager::create_wxglcanvas(wxWindow& parent)
     	WX_GL_SAMPLES, 			4,
     	0
     };
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 
     if (s_multisample == EMultisampleState::Unknown) {
         detect_multisample(attribList);
@@ -392,26 +411,26 @@ wxGLCanvas* OpenGLManager::create_wxglcanvas(wxWindow& parent)
 //        std::cout << "Multisample " << (can_multisample() ? "enabled" : "disabled") << std::endl;
     }
 
-    if (!can_multisample())
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
-#if ENABLE_GL_CORE_PROFILE
+    if (!can_multisample()) {
-    {
         attribList.Reset();
         attribList.PlatformDefaults().RGBA().DoubleBuffer().MinRGBA(8, 8, 8, 8).Depth(24).EndList();
     }
 
     return new wxGLCanvas(&parent, attribList, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxWANTS_CHARS);
 #else
+    if (!can_multisample())
         attribList[12] = 0;
 
     return new wxGLCanvas(&parent, wxID_ANY, attribList, wxDefaultPosition, wxDefaultSize, wxWANTS_CHARS);
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 }
 
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 void OpenGLManager::detect_multisample(const wxGLAttributes& attribList)
 #else
 void OpenGLManager::detect_multisample(int* attribList)
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 {
     int wxVersion = wxMAJOR_VERSION * 10000 + wxMINOR_VERSION * 100 + wxRELEASE_NUMBER;
     bool enable_multisample = wxVersion >= 30003;

src/slic3r/GUI/OpenGLManager.hpp

@@ -6,9 +6,9 @@
 class wxWindow;
 class wxGLCanvas;
 class wxGLContext;
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 class wxGLAttributes;
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 
 namespace Slic3r {
 namespace GUI {
@@ -49,6 +49,14 @@ public:
         bool is_mesa() const;
 #endif // _WIN32
 #endif // ENABLE_OPENGL_ES
+        bool is_es() {
+            return
+#if ENABLE_OPENGL_ES
+                true;
+#else
+                false;
+#endif // ENABLE_OPENGL_ES
+        }
 
         int get_max_tex_size() const;
         float get_max_anisotropy() const;
@@ -112,11 +120,11 @@ public:
     static const GLInfo& get_gl_info() { return s_gl_info; }
 
 private:
-#if ENABLE_GL_CORE_PROFILE
+#if ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
     static void detect_multisample(const wxGLAttributes& attribList);
 #else
     static void detect_multisample(int* attribList);
-#endif // ENABLE_GL_CORE_PROFILE
+#endif // ENABLE_GL_CORE_PROFILE || ENABLE_OPENGL_ES
 };
 
 } // namespace GUI