Shader mm_contour - Customizable offset to calculate the correction to avoid z-fighting (MESA driver needs bigger one)

resources/shaders/110/mm_contour.vs

@@ -2,6 +2,7 @@
 
 uniform mat4 view_model_matrix;
 uniform mat4 projection_matrix;
+uniform float offset;
 
 attribute vec3 v_position;
 
@@ -9,6 +10,6 @@ void main()
 {
     // Add small epsilon to z to solve z-fighting between painted triangles and contour lines.
 	vec4 clip_position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
-	clip_position.z -= 0.00001 * abs(clip_position.w);
+	clip_position.z -= offset * abs(clip_position.w);
     gl_Position = clip_position;
 }

resources/shaders/140/mm_contour.vs

@@ -2,6 +2,7 @@
 
 uniform mat4 view_model_matrix;
 uniform mat4 projection_matrix;
+uniform float offset;
 
 in vec3 v_position;
 
@@ -9,6 +10,6 @@ void main()
 {
     // Add small epsilon to z to solve z-fighting between painted triangles and contour lines.
 	vec4 clip_position = projection_matrix * view_model_matrix * vec4(v_position, 1.0);
-	clip_position.z -= 0.00001 * abs(clip_position.w);
+	clip_position.z -= offset * abs(clip_position.w);
     gl_Position = clip_position;
 }

resources/shaders/mm_contour.vs

@@ -1,9 +1,11 @@
 #version 110
 
+uniform float offset;
+
 void main()
 {
     // Add small epsilon to z to solve z-fighting between painted triangles and contour lines.
 	vec4 clip_position = gl_ModelViewProjectionMatrix * gl_Vertex;
-	clip_position.z -= 0.00001 * abs(clip_position.w);
+	clip_position.z -= offset * abs(clip_position.w);
     gl_Position = clip_position;
 }