Add support for projected falloff.

3 files changed, 42 insertions, 4 deletions

diff --git a/source/blender/gpu/shaders/sculpt_paint/infos/sculpt_paint_image_info.hh b/source/blender/gpu/shaders/sculpt_paint/infos/sculpt_paint_image_info.hh
index 1a834ff6516..97eed0237f4 100644
--- a/source/blender/gpu/shaders/sculpt_paint/infos/sculpt_paint_image_info.hh
+++ b/source/blender/gpu/shaders/sculpt_paint/infos/sculpt_paint_image_info.hh
@@ -18,9 +18,7 @@ GPU_SHADER_CREATE_INFO(sculpt_paint_image_compute)
     .push_constant(Type::INT, "pixel_row_offset")
     .push_constant(Type::IVEC2, "paint_step_range")
     .compute_source("sculpt_paint_image_comp.glsl")
-    .typedef_source("GPU_sculpt_shader_shared.h")
-    .define("BRUSH_TEST_SPHERE")
-    .do_static_compilation(true);
+    .typedef_source("GPU_sculpt_shader_shared.h");
 
 GPU_SHADER_CREATE_INFO(sculpt_paint_image_merge_compute)
     .local_group_size(1, 1, 1)
@@ -29,3 +27,21 @@ GPU_SHADER_CREATE_INFO(sculpt_paint_image_merge_compute)
     .compute_source("sculpt_paint_image_merge_comp.glsl")
     .typedef_source("GPU_sculpt_shader_shared.h")
     .do_static_compilation(true);
+
+/* -------------------------------------------------------------------- */
+/** \name Brush variations
+ * \{ */
+
+GPU_SHADER_CREATE_INFO(sculpt_paint_test_sphere).define("BRUSH_TEST_SPHERE");
+GPU_SHADER_CREATE_INFO(sculpt_paint_test_circle).define("BRUSH_TEST_CIRCLE");
+
+#define SCULPT_PAINT_FINAL_VARIATION(name, ...) \
+  GPU_SHADER_CREATE_INFO(name).additional_info(__VA_ARGS__).do_static_compilation(true);
+
+#define SCULPT_PAINT_TEST_VARIATIONS(name, ...) \
+  SCULPT_PAINT_FINAL_VARIATION(name##_sphere, "sculpt_paint_test_sphere", __VA_ARGS__) \
+  SCULPT_PAINT_FINAL_VARIATION(name##_circle, "sculpt_paint_test_circle", __VA_ARGS__)
+
+SCULPT_PAINT_TEST_VARIATIONS(sculpt_paint_image, "sculpt_paint_image_compute")
+
+/** \} */
diff --git a/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_comp.glsl b/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_comp.glsl
index 2a43b3c8ebc..e85e894a25b 100644
--- a/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_comp.glsl
+++ b/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_comp.glsl
@@ -5,8 +5,10 @@ bool SCULPT_brush_test(PaintBrushTestData test_data,
                        vec3 co,
                        out float dist)
 {
-#ifdef BRUSH_TEST_SPHERE
+#if defined(BRUSH_TEST_SPHERE)
   return SCULPT_brush_test_sphere(test_data, step_data, co, dist);
+#elif defined(BRUSH_TEST_CIRCLE)
+  return SCULPT_brush_test_circle(test_data, step_data, co, dist);
 #else
   dist = 0.0;
   return true;
diff --git a/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_lib.glsl b/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_lib.glsl
index bb6529fe966..159e24112d8 100644
--- a/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_lib.glsl
+++ b/source/blender/gpu/shaders/sculpt_paint/sculpt_paint_image_lib.glsl
@@ -7,6 +7,26 @@ bool SCULPT_brush_test_sphere(PaintBrushTestData test_data,
   return dist <= step_data.radius;
 }
 
+float plane_point_side_v3(vec4 plane, vec3 co)
+{
+  return dot(co, vec3(plane)) + plane.w;
+}
+
+vec3 closest_to_plane_normalized_v3(vec4 plane, vec3 co)
+{
+  float side = plane_point_side_v3(plane, co);
+  return (vec3(plane) * -side) + co;
+}
+
+bool SCULPT_brush_test_circle(PaintBrushTestData test_data,
+                              PaintStepData step_data,
+                              vec3 co,
+                              out float dist)
+{
+  vec3 proj = closest_to_plane_normalized_v3(step_data.plane_view, co);
+  return SCULPT_brush_test_sphere(test_data, step_data, proj, dist);
+}
+
 void SCULPT_get_row_pos_and_delta(vec3 co1,
                                   vec3 co2,
                                   vec3 co3,