Use vertex pulling for clouds

shader/pull/cloud.frag

@@ -0,0 +1,15 @@
+#version 450 core
+in vec3 vPos;
+in vec4 vCol;
+in vec2 vControls;
+layout (location=0) out vec4 fCol;
+layout (location=1) out vec4 fPos;
+layout (location=2) out vec4 fNorm;
+void main()
+{
+    float d = dot(vControls,vControls);
+    if (d > 1) {discard;}
+    fCol = vec4(vCol.xyz,vCol.w*(1-d));
+    fPos = vec4(vPos, vCol.w*(1-d));
+    fNorm = vec4(-vControls, -0.1 + 0.2 * d ,fPos.w);
+}

shader/pull/cloud.vert

@@ -0,0 +1,25 @@
+#version 450 core
+struct CloudPosCol { vec4 pos; vec4 col; };
+layout (std140, binding = 0) uniform TheMat { mat4 theMat; } ;
+layout (std430, binding = 6) readonly buffer CPos { CloudPosCol data[]; };
+const vec2 indices[6] = 
+    {vec2(-1,-1)  // 0    2--3
+    ,vec2( 1,-1)  // 1    |  |
+    ,vec2( 1, 1)  // 3    0--1
+    ,vec2(-1,-1)  // 0
+    ,vec2(-1, 1)  // 2
+    ,vec2( 1, 1)  // 3
+    };
+out vec4 vCol;
+out vec2 vControls;
+out vec3 vPos;
+void main()
+{
+    uint i = gl_VertexID / 6;
+    uint k = gl_VertexID % 6;
+    vCol = data[i].col;
+//    vCol = vec4(1,0.5,0,1);
+    vControls = indices[k];
+    vPos = vec3(data[i].pos.xy + 20*vControls, data[i].pos.z);
+    gl_Position = theMat * vec4(vPos,1);
+}

shader/pull/ellipse.vert

@@ -0,0 +1,18 @@
+#version 450 core
+struct Verx { vec4 pos; vec4 col; };
+layout (std140, binding = 0) uniform TheMat { mat4 theMat; } ;
+layout (std430, binding = 6) readonly buffer Pos { Verx data[]; };
+int indices[6] = {0,1,3,0,3,2};
+out vec4 vColC;
+out vec4 vColE;
+out vec4 vPos;
+out vec2 vDist;
+void main()
+{
+    uint i0 = gl_VertexID / 6;
+    uint k = indices[gl_VertexID % 6];
+    vec4 br = 
+  //gl_Position = theMat * vec4(pos,1);
+  gl_Position = vec4(pos,1);
+  vCol = col;
+}