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diff --git a/source/blender/compositor/realtime_compositor/shaders/compositor_morphological_distance_feather.glsl b/source/blender/compositor/realtime_compositor/shaders/compositor_morphological_distance_feather.glsl
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+++ b/source/blender/compositor/realtime_compositor/shaders/compositor_morphological_distance_feather.glsl
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+#pragma BLENDER_REQUIRE(gpu_shader_compositor_texture_utilities.glsl)
+
+/* The Morphological Distance Feather operation is a linear combination between the result of two
+ * operations. The first operation is a Gaussian blur with a radius equivalent to the dilate/erode
+ * distance, which is straightforward and implemented as a separable filter similar to the blur
+ * operation.
+ *
+ * The second operation is an approximation of a morphological inverse distance operation evaluated
+ * at a distance falloff function. The result of a morphological inverse distance operation is a
+ * narrow band distance field that starts at its maximum value at boundaries where a difference in
+ * values took place and linearly deceases until it reaches zero in the span of a number of pixels
+ * equivalent to the erode/dilate distance. Additionally, instead of linearly decreasing, the user
+ * may choose a different falloff which is evaluated at the computed distance. For dilation, the
+ * distance field decreases outwards, and for erosion, the distance field decreased inwards.
+ *
+ * The reason why the result of a Gaussian blur is mixed in with the distance field is because the
+ * distance field is merely approximated and not accurately computed, the defects of which is more
+ * apparent away from boundaries and especially at corners where the distance field should take a
+ * circular shape. That's why the Gaussian blur is mostly mixed only further from boundaries.
+ *
+ * The morphological inverse distance operation is approximated using a separable implementation
+ * and intertwined with the Gaussian blur implementation as follows. A search window of a radius
+ * equivalent to the dilate/erode distance is applied on the image to find either the minimum or
+ * maximum pixel value multiplied by its corresponding falloff value in the window. For dilation,
+ * we try to find the maximum, and for erosion, we try to find the minimum. Additionally, we also
+ * save the falloff value where the minimum or maximum was found. The found value will be that of
+ * the narrow band distance field and the saved falloff value will be used as the mixing factor
+ * with the Gaussian blur.
+ *
+ * To make sense of the aforementioned algorithm, assume we are dilating a binary image by 5 pixels
+ * whose half has a value of 1 and the other half has a value of zero. Consider the following:
+ *
+ * - A pixel of value 1 already has the maximum possible value, so its value will remain unchanged
+ *   regardless of its position.
+ * - A pixel of value 0 that is right at the boundary of the 1's region will have a maximum value
+ *   of around 0.8 depending on the falloff. That's because the search window intersects the 1's
+ *   region, which when multiplied by the falloff gives the first value of the falloff, which is
+ *   larger than the initially zero value computed at the center of the search window.
+ * - A pixel of value 0 that is 3 pixels away from the boundary will have a maximum value of around
+ *   0.4 depending on the falloff. That's because the search window intersects the 1's region,
+ *   which when multiplied by the falloff gives the third value of the falloff, which is larger
+ *   than the initially zero value computed at the center of the search window.
+ * - Finally, a pixel of value 0 that is 6 pixels away from the boundary will have a maximum value
+ *   of 0, because the search window doesn't intersects the 1's region and only spans zero values.
+ *
+ * The previous example demonstrates how the distance field naturally arises, and the same goes for
+ * the erode case, except the minimum value is computed instead.
+ */
+void main()
+{
+  ivec2 texel = ivec2(gl_GlobalInvocationID.xy);
+
+  /* A value for accumulating the blur result. */
+  float accumulated_value = 0.0;
+
+  /* Compute the contribution of the center pixel to the blur result. */
+  float center_value = texture_load(input_tx, texel).x;
+  accumulated_value += center_value * texture_load(weights_tx, 0).x;
+
+  /* Start with the center value as the maximum/minimum distance and reassign to the true maximum
+   * or minimum in the search loop below. Additionally, the center falloff is always 1.0, so start
+   * with that. */
+  float limit_distance = center_value;
+  float limit_distance_falloff = 1.0;
+
+  /* Compute the contributions of the pixels to the right and left, noting that the weights and
+   * falloffs textures only store the weights and falloffs for the positive half, but since the
+   * they are both symmetric, the same weights and falloffs are used for the negative half and we
+   * compute both of their contributions. */
+  for (int i = 1; i < texture_size(weights_tx); i++) {
+    float weight = texture_load(weights_tx, i).x;
+    float falloff = texture_load(falloffs_tx, i).x;
+
+    /* Loop for two iterations, where s takes the value of -1 and 1, which is used as the sign
+     * needed to evaluated the positive and negative sides as explain above. */
+    for (int s = -1; s < 2; s += 2) {
+      /* Compute the contribution of the pixel to the blur result. */
+      float value = texture_load(input_tx, texel + ivec2(s * i, 0)).x;
+      accumulated_value += value * weight;
+
+      /* The distance is computed such that its highest value is the pixel value itself, so
+       * multiply the distance falloff by the pixel value. */
+      float falloff_distance = value * falloff;
+
+      /* Find either the maximum or the minimum for the dilate and erode cases respectively. */
+      if (COMPARE(falloff_distance, limit_distance)) {
+        limit_distance = falloff_distance;
+        limit_distance_falloff = falloff;
+      }
+    }
+  }
+
+  /* Mix between the limit distance and the blurred accumulated value such that the limit distance
+   * is used for pixels closer to the boundary and the blurred value is used for pixels away from
+   * the boundary. */
+  float value = mix(accumulated_value, limit_distance, limit_distance_falloff);
+
+  /* Write the value using the transposed texel. See the execute_distance_feather_horizontal_pass
+   * method for more information on the rational behind this. */
+  imageStore(output_img, texel.yx, vec4(value));
+}