Render bezier curves using distance fields

shader/bezierQuad.vert

@@ -1,10 +1,10 @@
 #version 430 core
 layout (location = 0) in vec3 position;
 layout (location = 1) in vec4 color;
-layout (location = 2) in vec3 radVec;
+layout (location = 2) in vec4 boxes;
 out vec4 vColor;
-out vec2 vPosOff;
-out float vRadMag;
+out vec2 boxOut;
+out vec2 boxIn;
 
 uniform vec2 winSize;
 uniform float zoom;
@@ -16,6 +16,6 @@ void main()
 {
   gl_Position = worldMat * vec4(position.xyz,1);
   vColor  = color;
-  vPosOff = ( worldMat * vec4(radVec.xy,0,1) ).xy ;
-  vRadMag = radVec.z ;
+  boxOut = boxes.xy ;
+  boxIn = boxes.zw ;
 }