corner watertight

QTProject/subdivideRegular.tes

 #version 430
+#define M_PI 3.1415926535897932384626433832795
 layout(triangles, equal_spacing, cw) in;
 
 in vec3 tcPosition[];
@@ -10,6 +11,54 @@ uniform mat4x4 MV;
 uniform mat4x4 MVP;
 uniform int subdiv;
 
+bool compare(vec3 a, vec3 b){
+    if(a.x < b.x)
+        return true;
+    if(a.x > b.x)
+        return false;
+
+    if(a.y < b.y)
+        return true;
+    if(a.y > b.y)
+        return false;
+
+    if(a.z < b.z)
+        return true;
+    if(a.z > b.z)
+        return false;
+
+    return false;
+
+}
+
+vec3 calcCorner(vec3 points[6], vec3 center){
+    for(int i = 0; i < 5; i++){
+        for(int j = 0; j < 5-i; j++){
+            if(compare(points[j],points[j+1])){
+                vec3 temp = points[j];
+                points[j] = points[j+1];
+                points[j+1] = temp;
+            }
+        }
+    }
+
+    float a = 5.0/8.0 - pow((3.0 / 8.0 + 2.0/8.0 * cos(2.0 * M_PI / 6)), 2.0);
+    float omega = 3.0 * 6 / (8.0 * a);
+
+    vec3 newPos = vec3(0.0);
+
+    for (int i = 0; i < 6; i++) {
+        newPos += points[i];
+    }
+    newPos *= 1.0 / (omega + 6);
+    newPos += omega / (omega + 6) * center;
+
+
+    return newPos;
+}
+
+
+
 void main()
 {
     float u = gl_TessCoord.x;
@@ -55,39 +104,76 @@ void main()
 
     vec3 newPos= a0*p0+a1*p1+a2*p2+a3*p3+a4*p4+a5*p5+a6*p6+a7*p7+a8*p8+a9*p9+a10*p10+a11*p11;
 
-    if(v == 0){
-        newPos = (a0*p0+a11*p11)
-                   +(a1*p1+a10*p10)
-                   +(a4*p4+a6*p6)
-                   +(a2*p2+a8*p8)
-                   +(a3*p3+a7*p7);
-    }
+    //Edge
     if(u == 0){
         newPos = (a2*p2+a11*p11)
-                   +(a3*p3+a10*p10)
-                   +(a4*p4+a9*p9)
-                   +(a5*p5+a8*p8)
-                   +(a6*p6+a7*p7);
+            +(a3*p3+a10*p10)
+            +(a4*p4+a9*p9)
+            +(a5*p5+a8*p8)
+            +(a6*p6+a7*p7);
+    }
+    if(v == 0){
+        newPos = (a0*p0+a11*p11)
+            +(a1*p1+a10*p10)
+            +(a4*p4+a6*p6)
+            +(a2*p2+a8*p8)
+            +(a3*p3+a7*p7);
     }
+
     if(w == 0){
         newPos = (a0*p0+a10*p10)
-                   +(a3*p3+a6*p6)
-                   +(a1*p1+a9*p9)
-                   +(a5*p5+a4*p4)
-                   +(a2*p2+a7*p7);
+            +(a3*p3+a6*p6)
+            +(a1*p1+a9*p9)
+            +(a5*p5+a4*p4)
+            +(a2*p2+a7*p7);
     }
 
+    //Corner
+    if(u == 1){
+        vec3 points[6];
+        points[0] = p0;
+        points[1] = p1;
+        points[2] = p4;
+        points[3] = p7;
+        points[4] = p6;
+        points[5] = p2;
+
+        newPos= calcCorner(points, p3);
+    }
 
-    if (subdiv == 0) {
-        newPos = u * p3 + v * p6 + w * p7;
+    if(v == 1){
+        vec3 points[6];
+        points[0] = p2;
+        points[1] = p3;
+        points[2] = p7;
+        points[3] = p10;
+        points[4] = p9;
+        points[5] = p5;
+        newPos= calcCorner(points, p6);
     }
-    vec4 pos = vec4(newPos, 1.0f);
 
+    if(w == 1){
+        vec3 points[6];
+        points[0] = p3;
+        points[1] = p4;
+        points[2] = p8;
+        points[3] = p11;
+        points[4] = p10;
+        points[5] = p6;
+        newPos= calcCorner(points, p7);
+    }
 
 
 
+    if (subdiv == 0) {
+        newPos = u * p3 + v * p6 + w * p7;
+    }
+    vec4 pos = vec4(newPos, 1.0f);
+
     tePatchDistance = gl_TessCoord.xyz;
     teCamPosition = vec4(MV*pos).xyz;
     gl_Position = MVP * pos;
 }
 
+
+