1 files changed, 19 insertions, 0 deletions
diff --git a/source/blender/compositor/realtime_compositor/shaders/compositor_morphological_step.glsl b/source/blender/compositor/realtime_compositor/shaders/compositor_morphological_step.glsl
new file mode 100644
index 00000000000..6992bc2afa5
--- /dev/null
+++ b/source/blender/compositor/realtime_compositor/shaders/compositor_morphological_step.glsl
@@ -0,0 +1,19 @@
+#pragma BLENDER_REQUIRE(common_math_lib.glsl)
+#pragma BLENDER_REQUIRE(gpu_shader_compositor_texture_utilities.glsl)
+
+void main()
+{
+  ivec2 texel = ivec2(gl_GlobalInvocationID.xy);
+
+  /* Find the minimum/maximum value in the window of the given radius around the pixel. This is
+   * essentially a morphological operator with a square structuring element. The LIMIT value should
+   * be FLT_MAX if OPERATOR is min and FLT_MIN if OPERATOR is max. */
+  float value = LIMIT;
+  for (int i = -radius; i <= radius; i++) {
+    value = OPERATOR(value, texture_load(input_tx, texel + ivec2(i, 0), vec4(LIMIT)).x);
+  }
+
+  /* Write the value using the transposed texel. See the execute_step_horizontal_pass method for
+   * more information on the rational behind this. */
+  imageStore(output_img, texel.yx, vec4(value));
+}