Fix opengl core using -- remove GL_ALPHA to use texture with GL_RGBA

-- take more memory from GPU but works universaly(independent on opengl version)

src/slic3r/GUI/Gizmos/GLGizmoEmboss.cpp

@@ -1240,32 +1240,35 @@ void GLGizmoEmboss::init_face_names() {
     std::sort(m_face_names.names.begin(), m_face_names.names.end());
 }
 
-#include "slic3r/GUI/Jobs/CreateFontNameImageJob.hpp"
+// create texture for visualization font face
-void GLGizmoEmboss::draw_font_list()
+void GLGizmoEmboss::init_font_name_texture() {
-{
-    // Create of texture for font name
-    auto init_texture = [&face_names = m_face_names, size = m_gui_cfg->face_name_size]() {
     // check if already exists
-        GLuint &id = face_names.texture_id; 
+    GLuint &id = m_face_names.texture_id; 
     if (id != 0) return;
     // create texture for font
-        GLenum target = GL_TEXTURE_2D, format = GL_ALPHA,
+    GLenum target = GL_TEXTURE_2D;
-               type = GL_UNSIGNED_BYTE;
-        GLint level = 0, border = 0;
     glsafe(::glGenTextures(1, &id));
     glsafe(::glBindTexture(target, id));
     glsafe(::glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST));
     glsafe(::glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST));
-        GLint w = size.x(), h = face_names.names.size() * size.y();
+    const Vec2i &size = m_gui_cfg->face_name_size;
-        std::vector<unsigned char> data(w * h, {0});
+    GLint w = size.x(), h = m_face_names.names.size() * size.y();
-        glsafe(::glTexImage2D(target, level, GL_ALPHA, w, h, border, format, type, data.data()));
+    std::vector<unsigned char> data(4*w * h, {0});
+    const GLenum format = GL_RGBA, type = GL_UNSIGNED_BYTE;
+    const GLint level = 0, internal_format = GL_RGBA, border = 0;
+    glsafe(::glTexImage2D(target, level, internal_format, w, h, border, format, type, data.data()));
+
     // bind default texture
     GLuint no_texture_id = 0;
     glsafe(::glBindTexture(target, no_texture_id));
 
     // no one is initialized yet
-        face_names.exist_textures = std::vector<bool>(face_names.names.size(), {false});
+    m_face_names.exist_textures = std::vector<bool>(m_face_names.names.size(), {false});
-    };
+}
+
+#include "slic3r/GUI/Jobs/CreateFontNameImageJob.hpp"
+void GLGizmoEmboss::draw_font_list()
+{
     auto init_trancated_names = [&face_names = m_face_names, 
         width = m_gui_cfg->face_name_max_width]() { 
         if (!face_names.names_truncated.empty()) return;
@@ -1288,7 +1291,7 @@ void GLGizmoEmboss::draw_font_list()
     wxString del_facename;
     if (ImGui::BeginCombo("##font_selector", selected)) {
         if (!m_face_names.is_init) init_face_names();
-        init_texture();
+        init_font_name_texture();
         if (m_face_names.names_truncated.empty()) init_trancated_names();
         ImTextureID tex_id = (void *) (intptr_t) m_face_names.texture_id;
         for (const wxString &face_name : m_face_names.names) {
@@ -1309,6 +1312,11 @@ void GLGizmoEmboss::draw_font_list()
                 ImGui::IsItemVisible()) {
                 m_face_names.exist_textures[index] = true;
                 std::string text = m_text.empty() ? "AaBbCc" : m_text;
+                                
+                const unsigned char gray_level = 5;
+                // format type and level must match to texture data
+                const GLenum format = GL_RGBA, type = GL_UNSIGNED_BYTE;
+                const GLint level = 0;
                 // render text to texture
                 FontImageData data{text,
                                    face_name,
@@ -1316,8 +1324,11 @@ void GLGizmoEmboss::draw_font_list()
                                    m_face_names.texture_id,
                                    index,
                                    m_gui_cfg->face_name_size,
-                                   &m_allow_update_rendered_font
+                                   &m_allow_update_rendered_font,
-                };
+                                   gray_level,
+                                   format,
+                                   type,
+                                   level};
                 auto job = std::make_unique<CreateFontImageJob>(std::move(data));
                 auto& worker = wxGetApp().plater()->get_ui_job_worker();
                 queue_job(worker, std::move(job));
@@ -1767,7 +1778,7 @@ void GLGizmoEmboss::draw_style_list() {
             bool is_selected = (index == m_style_manager.get_style_index());
 
             ImVec2 select_size(0,m_gui_cfg->max_style_image_size.y()); // 0,0 --> calculate in draw
-            const std::optional<EmbossStyleManager::StyleImage> img = item.image;            
+            const std::optional<EmbossStyleManager::StyleImage> &img = item.image;            
             // allow click delete button
             ImGuiSelectableFlags_ flags = ImGuiSelectableFlags_AllowItemOverlap; 
             if (ImGui::Selectable(item.truncated_name.c_str(), is_selected, flags, select_size)) {

src/slic3r/GUI/Gizmos/GLGizmoEmboss.hpp

@@ -108,6 +108,7 @@ private:
     void draw_style_save_button(bool is_modified);
     void draw_style_save_as_popup();
     void draw_style_add_button();
+    void init_font_name_texture();
     void draw_font_list();
     void draw_style_edit();
     bool draw_italic_button();

src/slic3r/GUI/Jobs/CreateFontNameImageJob.cpp

@@ -62,7 +62,7 @@ void CreateFontImageJob::process(Ctl &ctl)
     if (m_tex_size.x() > m_input.size.x()) m_tex_size.x() = m_input.size.x();
 
     // Set up result
-    m_result = std::vector<unsigned char>(m_tex_size.x() * m_tex_size.y(), {0});
+    m_result = std::vector<unsigned char>(m_tex_size.x() * m_tex_size.y() * 4, {255});
 
     sla::Resolution resolution(m_tex_size.x(), m_tex_size.y());
     double pixel_dim = SCALING_FACTOR / scale;
@@ -85,7 +85,7 @@ void CreateFontImageJob::process(Ctl &ctl)
                 size_t index = y*w + x;
                 assert(index < size);
                 if (index >= size) continue;
-                pix[index] = ptr2[y * width + x] / gray_level;
+                pix[3+4*index] = ptr2[y * width + x] / gray_level;
             }
         return sla::EncodedRaster();
     };

src/slic3r/GUI/Jobs/CreateFontStyleImagesJob.cpp

@@ -89,7 +89,7 @@ void CreateFontStyleImagesJob::process(Ctl &ctl)
     }
 
     // Set up result
-    pixels = std::vector<unsigned char>(width * height, {0});
+    pixels = std::vector<unsigned char>(4*width * height, {255});
 
     // upload sub textures
     for (EmbossStyleManager::StyleImage &image : images) {
@@ -116,7 +116,7 @@ void CreateFontStyleImagesJob::process(Ctl &ctl)
                     size_t index = (offset.y() + y)*w + offset.x() + x;
                     assert(index < size);
                     if (index >= size) continue;
-                    pix[index] = ptr2[y * width + x] / gray_level;
+                    pix[4*index+3] = ptr2[y * width + x] / gray_level;
                 }
             return sla::EncodedRaster();
         };
@@ -128,14 +128,14 @@ void CreateFontStyleImagesJob::finalize(bool canceled, std::exception_ptr &)
 {
     // upload texture on GPU
     GLuint tex_id;
-    GLenum target = GL_TEXTURE_2D, format = GL_ALPHA, type = GL_UNSIGNED_BYTE;
+    GLenum target = GL_TEXTURE_2D, format = GL_RGBA, type = GL_UNSIGNED_BYTE;
     GLint  level = 0, border = 0;
     glsafe(::glGenTextures(1, &tex_id));
     glsafe(::glBindTexture(target, tex_id));
     glsafe(::glTexParameteri(target, GL_TEXTURE_MIN_FILTER, GL_NEAREST));
     glsafe(::glTexParameteri(target, GL_TEXTURE_MAG_FILTER, GL_NEAREST));
     GLint w = width, h=height;
-    glsafe(::glTexImage2D(target, level, GL_ALPHA, w, h, border, format, type,
+    glsafe(::glTexImage2D(target, level, GL_RGBA, w, h, border, format, type,
                           (const void *) pixels.data()));
 
     // set up texture id

src/slic3r/Utils/EmbossStyleManager.cpp

@@ -346,10 +346,7 @@ void EmbossStyleManager::init_style_images(const Vec2i &max_size,
 
 void EmbossStyleManager::free_style_images() {
     if (!m_exist_style_images) return;
-    if (!is_activ_font()) return;
-
     GLuint tex_id = 0;
-    
     for (Item &it : m_style_items) {
         if (tex_id == 0 && it.image.has_value())
             tex_id = (GLuint)(intptr_t) it.image->texture_id;
@@ -475,6 +472,5 @@ bool EmbossStyleManager::set_wx_font(const wxFont &wx_font, std::unique_ptr<Embo
     // update string path
     style.path = WxFontUtils::store_wxFont(wx_font);
     clear_imgui_font();
-    free_style_images();
     return true;
 }