Edit Mesh: Refactor edit mesh drawing

This decouple the vertex display from the face+edges.

This is to reduce the number of triangles required to fix the edges
artifacts (aliasing) and increase viewport reactivity when not actively
navigating (ie. mouse scroll).

Also it makes all vertices visible (not cut-off) even when navigating.

However it makes the navigation drawing a bit slower because it has to
render twice.

Also add a depth bias to the wires to avoid depth fighting when previewing
final mesh (modifiers applied).

1 files changed, 77 insertions, 12 deletions

diff --git a/source/blender/draw/modes/shaders/edit_mesh_overlay_vert.glsl b/source/blender/draw/modes/shaders/edit_mesh_overlay_vert.glsl
index 7cab2a5035f..8715ab69181 100644
--- a/source/blender/draw/modes/shaders/edit_mesh_overlay_vert.glsl
+++ b/source/blender/draw/modes/shaders/edit_mesh_overlay_vert.glsl
@@ -2,38 +2,103 @@
 /* Solid Wirefram implementation
  * Mike Erwin, Clément Foucault */
 
-/* This shader follows the principles of
- * http://developer.download.nvidia.com/SDK/10/direct3d/Source/SolidWireframe/Doc/SolidWireframe.pdf */
-
+uniform mat3 NormalMatrix;
+uniform mat4 ProjectionMatrix;
 uniform mat4 ModelViewMatrix;
 uniform mat4 ModelViewProjectionMatrix;
 uniform ivec4 dataMask = ivec4(0xFF);
 
+uniform float ofs = 1e-5;
+
+uniform isamplerBuffer dataBuffer;
+
 in vec3 pos;
+#ifdef VERTEX_FACING
+in vec3 vnor;
+#endif
+
+#ifdef EDGE_FIX
 in ivec4 data;
 
 out vec4 vPos;
 out vec4 pPos;
 out ivec4 vData;
-
-#ifdef VERTEX_FACING
-uniform mat4 ProjectionMatrix;
-uniform mat3 NormalMatrix;
-
-in vec3 vnor;
+#  ifdef VERTEX_FACING
 out float vFacing;
-#endif
+#  endif
 
 void main()
 {
 	vPos = ModelViewMatrix * vec4(pos, 1.0);
 	pPos = ModelViewProjectionMatrix * vec4(pos, 1.0);
+	pPos.z -= ofs;
 	vData = data & dataMask;
-#ifdef VERTEX_FACING
+#  ifdef VERTEX_FACING
 	vec3 view_normal = normalize(NormalMatrix * vnor);
 	vec3 view_vec = (ProjectionMatrix[3][3] == 0.0)
 		? normalize(vPos.xyz)
 		: vec3(0.0, 0.0, 1.0);
 	vFacing = dot(view_vec, view_normal);
-#endif
+#  endif
 }
+
+#else /* EDGE_FIX */
+
+flat out vec3 edgesCrease;
+flat out vec3 edgesBweight;
+flat out vec4 faceColor;
+flat out ivec3 flag;
+#  ifdef VERTEX_SELECTION
+out vec3 vertexColor;
+#  endif
+#  ifdef VERTEX_FACING
+out float facing;
+#  endif
+
+out vec3 barycentric;
+
+void main()
+{
+	gl_Position = ModelViewProjectionMatrix * vec4(pos, 1.0);
+	gl_Position.z -= ofs;
+
+	int v_0 = (gl_VertexID / 3) * 3;
+	int vidx = gl_VertexID % 3;
+	barycentric = vec3(0.0);
+	barycentric[vidx] = 1.0;
+
+	/* Edge */
+	ivec4 vData[3], data = ivec4(0);
+	ivec3 eflag;
+	for (int v = 0; v < 3; ++v) {
+		data = texelFetch(dataBuffer, v_0 + v);
+		vData[v] = data & dataMask;
+		flag[v] = eflag[v] = vData[v].y | (vData[v].x << 8);
+		edgesCrease[v] = vData[v].z / 255.0;
+		edgesBweight[v] = vData[v].w / 255.0;
+	}
+
+	/* Face */
+	if ((vData[0].x & FACE_ACTIVE) != 0)
+		faceColor = colorFaceSelect;
+	else if ((vData[0].x & FACE_SELECTED) != 0)
+		faceColor = colorFaceSelect;
+	else if ((vData[0].x & FACE_FREESTYLE) != 0)
+		faceColor = colorFaceFreestyle;
+	else
+		faceColor = colorFace;
+
+#  ifdef VERTEX_SELECTION
+	vertexColor = EDIT_MESH_vertex_color(vData[vidx].x).rgb;
+#  endif
+#  ifdef VERTEX_FACING
+	vec4 vPos = ModelViewMatrix * vec4(pos, 1.0);
+	vec3 view_normal = normalize(NormalMatrix * vnor);
+	vec3 view_vec = (ProjectionMatrix[3][3] == 0.0)
+		? normalize(vPos.xyz)
+		: vec3(0.0, 0.0, 1.0);
+	facing = dot(view_vec, view_normal);
+#  endif
+}
+
+#endif
\ No newline at end of file