1 files changed, 33 insertions, 41 deletions

diff --git a/source/blender/draw/modes/shaders/armature_shape_outline_geom.glsl b/source/blender/draw/modes/shaders/armature_shape_outline_geom.glsl
index dc7ed5e202a..11924b19cf8 100644
--- a/source/blender/draw/modes/shaders/armature_shape_outline_geom.glsl
+++ b/source/blender/draw/modes/shaders/armature_shape_outline_geom.glsl
@@ -1,11 +1,9 @@
 
-/* TODO: See perf with multiple invocations. */
-layout(triangles_adjacency) in;
-layout(triangle_strip, max_vertices = 16) out;
+layout(lines_adjacency) in;
+layout(triangle_strip, max_vertices = 6) out;
 
 in vec4 pPos[];
-in float vZ[];
-in float vFacing[];
+in vec3 vPos[];
 in vec2 ssPos[];
 in vec2 ssNor[];
 in vec4 vColSize[];
@@ -22,21 +20,18 @@ vec2 compute_dir(vec2 v0, vec2 v1)
 	return dir;
 }
 
-void emit_edge(const ivec3 edges, vec2 thick, bool is_persp)
+void emit_edge(vec2 edge_dir, vec2 hidden_dir, vec2 thick, bool is_persp)
 {
-	vec2 edge_dir = compute_dir(ssPos[edges.x], ssPos[edges.y]);
-	vec2 hidden_dir = normalize(ssPos[edges.z] - ssPos[edges.x]);
-
 	float fac = dot(-hidden_dir, edge_dir);
 
-	vec2 t = thick * (is_persp ? vZ[edges.x] : 1.0);
-	gl_Position = pPos[edges.x];
+	vec2 t = thick * (is_persp ? abs(vPos[1].z) : 1.0);
+	gl_Position = pPos[1];
 	EmitVertex();
 	gl_Position.xy += t * edge_dir * sign(fac);
 	EmitVertex();
 
-	t = thick * (is_persp ? vZ[edges.y] : 1.0);
-	gl_Position = pPos[edges.y];
+	t = thick * (is_persp ? abs(vPos[2].z) : 1.0);
+	gl_Position = pPos[2];
 	EmitVertex();
 	gl_Position.xy += t * edge_dir * sign(fac);
 	EmitVertex();
@@ -45,7 +40,7 @@ void emit_edge(const ivec3 edges, vec2 thick, bool is_persp)
 void emit_corner(const int e, vec2 thick, bool is_persp)
 {
 	vec2 corner_dir = ssNor[e];
-	vec2 t = thick * (is_persp ? vZ[e] : 1.0);
+	vec2 t = thick * (is_persp ? abs(vPos[e].z) : 1.0);
 
 	gl_Position = pPos[e] + vec4(t * corner_dir, 0.0, 0.0);
 	EmitVertex();
@@ -55,41 +50,38 @@ void main(void)
 {
 	finalColor = vec4(vColSize[0].rgb, 1.0);
 
-	vec2 thick = vColSize[0].w * (lineThickness / viewportSize);
 	bool is_persp = (ProjectionMatrix[3][3] == 0.0);
 
-	const ivec3 edges = ivec3(0, 2, 4);
-	vec4 facing = vec4(vFacing[1], vFacing[3], vFacing[5], vFacing[0]);
-	bvec4 do_edge = greaterThanEqual(facing, vec4(0.0));
+	vec3 view_vec = (is_persp) ? normalize(vPos[1]) : vec3(0.0, 0.0, -1.0);
+	vec3 v10 = vPos[0] - vPos[1];
+	vec3 v12 = vPos[2] - vPos[1];
+	vec3 v13 = vPos[3] - vPos[1];
 
-	/* Only generate outlines from backfaces. */
-	if (do_edge.w)
-		return;
+	vec3 n0 = cross(v12, v10);
+	vec3 n3 = cross(v13, v12);
 
-	if (do_edge.x) {
-		emit_corner(edges.x, thick, is_persp);
-		emit_edge(edges.xyz, thick, is_persp);
-	}
+	float fac0 = dot(view_vec, n0);
+	float fac3 = dot(view_vec, n3);
 
-	if (any(do_edge.xy)) {
-		emit_corner(edges.y, thick, is_persp);
-	}
+	/* If both adjacent verts are facing the camera the same way,
+	 * then it isn't an outline edge. */
+	if (sign(fac0) == sign(fac3))
+		return;
 
-	if (do_edge.y) {
-		emit_edge(edges.yzx, thick, is_persp);
-	}
-	else {
-		EndPrimitive();
-	}
+	/* Don't outline if concave edge. */
+	if (dot(n0, v13) > 0.0)
+		return;
 
-	if (any(do_edge.yz)) {
-		emit_corner(edges.z, thick, is_persp);
-	}
+	vec2 thick = vColSize[0].w * (lineThickness / viewportSize);
+	vec2 edge_dir = compute_dir(ssPos[1], ssPos[2]);
 
-	if (do_edge.z) {
-		emit_edge(edges.zxy, thick, is_persp);
-		emit_corner(edges.x, thick, is_persp);
-	}
+	/* Take the farthest point to compute edge direction
+	 * (avoid problems with point behind near plane). */
+	vec2 hidden_point = (vPos[0].z < vPos[3].z) ? ssPos[0] : ssPos[3];
+	vec2 hidden_dir = normalize(hidden_point - ssPos[1]);
 
+	emit_corner(1, thick, is_persp);
+	emit_edge(edge_dir, hidden_dir, thick, is_persp);
+	emit_corner(2, thick, is_persp);
 	EndPrimitive();
 }