Object Mode Outline: Changed algorithm a bit.

First pass find outline pixel.
Second pass expand it by 1px in each direction.
Subsequent passes fade the occluded outlines inward.

1 files changed, 18 insertions, 42 deletions

diff --git a/source/blender/draw/modes/shaders/object_outline_expand_frag.glsl b/source/blender/draw/modes/shaders/object_outline_expand_frag.glsl
index 73b9e7f1f0c..b57c4f5ea0e 100644
--- a/source/blender/draw/modes/shaders/object_outline_expand_frag.glsl
+++ b/source/blender/draw/modes/shaders/object_outline_expand_frag.glsl
@@ -4,66 +4,42 @@ in vec4 uvcoordsvar;
 out vec4 FragColor;
 
 uniform sampler2D outlineColor;
-#ifdef DEPTH_TEST
 uniform sampler2D outlineDepth;
-uniform sampler2D sceneDepth;
-#endif
 
 uniform float alpha;
+uniform bool doExpand;
 
-#define ALPHA_OCCLU 0.4
-
-void search_outline(ivec2 uv, ivec2 offset, inout float weight, inout vec4 col_accum)
+void search_outline(ivec2 uv, ivec2 offset, inout bool found_edge)
 {
-	vec4 color = texelFetchOffset(outlineColor, uv, 0, offset).rgba;
-	if (color.a != 0.0) {
-#ifdef DEPTH_TEST
-		/* Modulate color if occluded */
-		/* TODO bias in linear depth not exponential */
-		float depth = texelFetchOffset(outlineDepth, uv, 0, offset).r;
-		float scene_depth = texelFetchOffset(sceneDepth, uv, 0, offset).r;
-		if (depth > scene_depth) {
-			color *= ALPHA_OCCLU;
+	if (!found_edge) {
+		vec4 color = texelFetchOffset(outlineColor, uv, 0, offset).rgba;
+		if (color.a != 0.0) {
+			if (doExpand || color.a != 1.0) {
+				FragColor = color;
+				found_edge = true;
+			}
 		}
-#endif
-		col_accum += color;
-		weight += 1.0;
 	}
 }
 
 void main()
 {
 	ivec2 uv = ivec2(gl_FragCoord.xy);
-	// vec2 uv = uvcoordsvar.xy + 0.5 / viewportSize;
 	FragColor = texelFetch(outlineColor, uv, 0).rgba;
+	float depth = texelFetch(outlineDepth, uv, 0).r;
 
-	if (FragColor.a != 0.0){
-#ifdef DEPTH_TEST
-		/* Modulate color if occluded */
-		float depth = texelFetch(outlineDepth, uv, 0).r;
-		float scene_depth = texelFetch(sceneDepth, uv, 0).r;
-		/* TODO bias in linear depth not exponential */
-		if (depth > scene_depth) {
-			FragColor *= ALPHA_OCCLU;
-		}
-#endif
+	if (FragColor.a != 0.0 || (depth == 1.0 && !doExpand))
 		return;
-	}
 
-	float weight = 0.0;
-	vec4 col = vec4(0.0);
-
-	search_outline(uv, ivec2( 1,  0), weight, col);
-	search_outline(uv, ivec2( 0,  1), weight, col);
-	search_outline(uv, ivec2(-1,  0), weight, col);
-	search_outline(uv, ivec2( 0, -1), weight, col);
+	bool found_edge = false;
+	search_outline(uv, ivec2( 1,  0), found_edge);
+	search_outline(uv, ivec2( 0,  1), found_edge);
+	search_outline(uv, ivec2(-1,  0), found_edge);
+	search_outline(uv, ivec2( 0, -1), found_edge);
 
 	/* We Hit something ! */
-	if (weight != 0.0) {
-		FragColor = col / weight;
+	if (found_edge) {
+		/* only change alpha */
 		FragColor.a *= alpha;
 	}
-	else {
-		FragColor = vec4(0.0);
-	}
 }