From b39df3e6fe7b80a177a000b5f85bef483b15f771 Mon Sep 17 00:00:00 2001
From: Filip Sykala - NTB T15p <Filip.Sykala@Prusa3D.cz>
Date: Mon, 19 Aug 2024 16:33:54 +0200
Subject: [PATCH] Add comments

---
 src/libslic3r/SLA/SupportPointGenerator.cpp | 2 ++
 src/libslic3r/SLA/SupportPointGenerator.hpp | 7 ++++++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/libslic3r/SLA/SupportPointGenerator.cpp b/src/libslic3r/SLA/SupportPointGenerator.cpp
index 227cc61c16..d506e7e0eb 100644
--- a/src/libslic3r/SLA/SupportPointGenerator.cpp
+++ b/src/libslic3r/SLA/SupportPointGenerator.cpp
@@ -147,6 +147,8 @@ static std::vector<SupportPointGenerator::MyLayer> make_layers(
         SupportPointGenerator::MyLayer &layer   = layers[layer_id];
         const ExPolygons &              islands = slices[layer_id];
         // FIXME WTF?
+        // It is used only for support point Z coordinate.
+        // Possibly some kind of big foot compensation ??
         const float height = (layer_id > 2 ?
                                   heights[layer_id - 3] :
                                   heights[0] - (heights[1] - heights[0]));
diff --git a/src/libslic3r/SLA/SupportPointGenerator.hpp b/src/libslic3r/SLA/SupportPointGenerator.hpp
index 734c09bef1..c01e4ea7aa 100644
--- a/src/libslic3r/SLA/SupportPointGenerator.hpp
+++ b/src/libslic3r/SLA/SupportPointGenerator.hpp
@@ -55,6 +55,7 @@ public:
     
     struct MyLayer;
     
+    // Keep data for one area(ExPlygon) on the layer
     struct Structure {
         Structure(MyLayer &layer, const ExPolygon& poly, const BoundingBox &bbox, const Vec2f &centroid, float area, float h) :
             layer(&layer), polygon(&poly), bbox(bbox), centroid(centroid), area(area), zlevel(h)
@@ -62,7 +63,9 @@ public:
             , unique_id(std::chrono::duration_cast<std::chrono::milliseconds>(std::chrono::system_clock::now().time_since_epoch()))
 #endif /* SLA_SUPPORTPOINTGEN_DEBUG */
         {}
+        // Parent layer - with all ExPolygons in layer + layer_height
         MyLayer *layer;
+        // Source ExPolygon
         const ExPolygon* polygon = nullptr;
         const BoundingBox bbox;
         const Vec2f centroid = Vec2f::Zero();
@@ -143,8 +146,10 @@ public:
     
     struct MyLayer {
         MyLayer(const size_t layer_id, coordf_t print_z) : layer_id(layer_id), print_z(print_z) {}
+        // index into heights + slices
         size_t                  layer_id;
-        coordf_t                print_z;
+        // Absolute distance from Zero - copy value from heights<float>
+        coordf_t print_z; // [in mm]
         std::vector<Structure>  islands;
     };