Implement color for quadratic bezier curves

shader/bezierQuad.frag

@@ -1,6 +1,8 @@
 #version 430 core
 in vec4 gColor;
 in vec3 gBoundingBox;
+in float gRadStart;
+in float gRadEnd;
 
 out vec4 fColor;
 
@@ -8,7 +10,8 @@ float x = gBoundingBox.x;
 float y = gBoundingBox.y;
 float z = gBoundingBox.z;
 
-float w = 0.1;
+float w = gRadEnd;
+float w2 = gRadStart;
 
 float f (float a, float b)
 {   
@@ -17,10 +20,9 @@ float f (float a, float b)
 }
 void main()
 {
-
   //float d = x - y - 1 + 2* sqrt(y);
   float d = sqrt(x) + sqrt(y) - 1;
-  float e = sqrt(f(x,w)) + sqrt(f(y,w)) - 1;
+  float e = sqrt(f(x,w)) + sqrt(f(y,w2)) - 1.0;
   if ( d < 0 || e > 0) { discard; }
   fColor = gColor;
 //  if ( d < 0) { fColor = vec4 (0,1,0,1); }

shader/bezierQuad.geom

@@ -2,7 +2,10 @@
 layout (triangles) in;
 layout (triangle_strip, max_vertices = 3) out;
 in vec4 vColor[];
+in float vRad[];
 out vec4 gColor;
+out float gRadStart;
+out float gRadEnd;
 out vec3 gBoundingBox;
 
 void main()
@@ -11,6 +14,8 @@ void main()
   vec3 pb = gl_in[1].gl_Position.xyz;
   vec3 pc = gl_in[2].gl_Position.xyz;
 
+  gRadStart = vRad[0];
+  gRadEnd   = vRad[2];
 //  vec3 pa = vec3(paa.xy + 0.1 * (paa.xy - pca.xy), paa.z);
 //  vec3 pc = vec3(pca.xy + 0.1 * (pca.xy - paa.xy), pca.z);
 

shader/bezierQuad.vert

@@ -1,7 +1,9 @@
 #version 430 core
 layout (location = 0) in vec3 position;
 layout (location = 1) in vec4 color;
+layout (location = 2) in float rad;
 out vec4 vColor;
+out float vRad;
 
 uniform vec2 winSize;
 uniform float zoom;
@@ -13,4 +15,5 @@ void main()
 {
   gl_Position = worldMat * vec4(position.xyz,1);
   vColor = color;
+  vRad   = rad;
 }