ADDING SMOOTHNESS VIA TESSELLATION SHADERS

avogadro/rendering/CMakeLists.txt

@@ -106,6 +106,8 @@ set(shader_files
   "mesh_fs.glsl"
   "mesh_opaque_fs.glsl"
   "mesh_vs.glsl"
+  "mesh_tcs.glsl"
+  "mesh_tev.glsl"
   "solid_vs.glsl"
   "solid_first_fs.glsl"
   "spheres_fs.glsl"

avogadro/rendering/mesh_fs.glsl

@@ -1,17 +1,23 @@
-varying vec3 fnormal;
+#version 400
+precision highp float;
+
+in vec3 teNormal;
+in vec4 teColor;
+
+out vec4 colorOut;
 
 void main()
 {
-  vec3 N = normalize(fnormal);
-  vec3 L = normalize(vec3(0, 1, 1));
-  vec3 E = vec3(0, 0, 1);
-  vec3 H = normalize(L + E);
-  float df = max(0.0, dot(N, L));
-  float sf = max(0.0, dot(N, H));
-  sf = pow(sf, 20.0);
-  vec4 ambient = gl_Color / 3.0;
-  vec4 diffuse = gl_Color;
-  vec4 specular = gl_Color * 3.0;
-  gl_FragColor = ambient + df * diffuse + sf * specular;
-  gl_FragColor.a = gl_Color.a;
+    vec3 N = normalize(teNormal); 
+    vec3 L = normalize(vec3(0, 1, 1));
+    vec3 E = vec3(0, 0, 1);
+    vec3 H = normalize(L + E);
+    float df = max(0.0, dot(N, L));
+    float sf = max(0.0, dot(N, H));
+    sf = pow(sf, 20.0);
+    vec4 ambient = teColor / 3.0;
+    vec4 diffuse = teColor;
+    vec4 specular = teColor * 3.0;
+    colorOut = ambient + df * diffuse + sf * specular;
+    colorOut.a = teColor.a; 
 }

avogadro/rendering/mesh_opaque_fs.glsl

@@ -1,17 +1,24 @@
-varying vec3 fnormal;
+#version 400
+precision highp float;
+
+in vec3 teNormal;
+in vec4 teColor;
+
+out vec4 colorOut;
+
 
 void main()
 {
-  vec3 N = normalize(fnormal);
-  vec3 L = normalize(vec3(0, 1, 1));
-  vec3 E = vec3(0, 0, 1);
-  vec3 H = normalize(L + E);
-  float df = max(0.0, dot(N, -L));
-  float sf = max(0.0, dot(N, -H));
-  sf = pow(sf, 32.0);
-  vec4 ambient = gl_Color / 2.2;
-  vec4 diffuse = gl_Color * 1.1;
-  vec4 specular = gl_Color * 5.0;
-  gl_FragColor = ambient + df * diffuse + sf * specular;
-  gl_FragColor.a = gl_Color.a;
+    vec3 N = normalize(teNormal);
+    vec3 L = normalize(vec3(0.0, 1.0, 1.0));
+    vec3 E = vec3(0.0, 0.0, 1.0);
+    vec3 H = normalize(L + E);
+    float df = max(0.0, dot(N, -L));
+    float sf = max(0.0, dot(N, -H));
+    sf = pow(sf, 20.0);
+    vec4 ambient = teColor / 2.2;
+    vec4 diffuse = teColor * 1.1;
+    vec4 specular = teColor * 5.0;
+    colorOut = ambient + df * diffuse + sf * specular;
+    colorOut.a = teColor.a;
 }

avogadro/rendering/mesh_tcs.glsl

@@ -0,0 +1,83 @@
+#version 400
+precision highp float;
+
+layout(vertices = 1) out;
+
+in vec3 vsNormal[];
+in vec3 WorldPos_CS_in[];          
+in vec2 TexCoord_CS_in[];
+in vec3 teVertex[];
+in vec4 vsColor[];
+
+patch out vec3 WorldPos_B030;
+patch out vec3 WorldPos_B012;
+patch out vec3 WorldPos_B021;
+patch out vec3 WorldPos_B003;
+patch out vec3 WorldPos_B102;
+patch out vec3 WorldPos_B201;
+patch out vec3 WorldPos_B300;
+patch out vec3 WorldPos_B210;
+patch out vec3 WorldPos_B120;
+patch out vec3 WorldPos_B111;
+
+patch out vec2 tcsVertex[3];
+patch out vec3 tcsNormal[3];
+patch out vec3 tevVertex[3];
+patch out vec4 tcsColor[3];
+
+vec3 ProjectToPlane(vec3 Point, vec3 PlanePoint, vec3 PlaneNormal)
+{
+    vec3 v = Point - PlanePoint;
+    float Len = dot(v, PlaneNormal);
+    vec3 d = Len * PlaneNormal;
+    return (Point - d);
+}
+
+void CalcPositions()
+{
+    WorldPos_B030 = WorldPos_CS_in[0];
+    WorldPos_B003 = WorldPos_CS_in[1];
+    WorldPos_B300 = WorldPos_CS_in[2];
+
+    vec3 EdgeB300 = WorldPos_B003 - WorldPos_B030;
+    vec3 EdgeB030 = WorldPos_B300 - WorldPos_B003;
+    vec3 EdgeB003 = WorldPos_B030 - WorldPos_B300;
+
+    WorldPos_B021 = WorldPos_B030 + EdgeB300 / 3.0;
+    WorldPos_B012 = WorldPos_B030 + EdgeB300 * 2.0 / 3.0;
+    WorldPos_B102 = WorldPos_B003 + EdgeB030 / 3.0;
+    WorldPos_B201 = WorldPos_B003 + EdgeB030 * 2.0 / 3.0;
+    WorldPos_B210 = WorldPos_B300 + EdgeB003 / 3.0;
+    WorldPos_B120 = WorldPos_B300 + EdgeB003 * 2.0 / 3.0;
+
+    WorldPos_B021 = ProjectToPlane(WorldPos_B021, WorldPos_B030, normalize(vsNormal[0]));
+    WorldPos_B012 = ProjectToPlane(WorldPos_B012, WorldPos_B003, normalize(vsNormal[1]));
+    WorldPos_B102 = ProjectToPlane(WorldPos_B102, WorldPos_B003, normalize(vsNormal[1]));
+    WorldPos_B201 = ProjectToPlane(WorldPos_B201, WorldPos_B300, normalize(vsNormal[2]));
+    WorldPos_B210 = ProjectToPlane(WorldPos_B210, WorldPos_B300, normalize(vsNormal[2]));
+    WorldPos_B120 = ProjectToPlane(WorldPos_B120, WorldPos_B030, normalize(vsNormal[0]));
+
+    vec3 Center = (WorldPos_B003 + WorldPos_B030 + WorldPos_B300) / 3.0;
+    WorldPos_B111 = (WorldPos_B021 + WorldPos_B012 + WorldPos_B102 +
+                     WorldPos_B201 + WorldPos_B210 + WorldPos_B120) / 6.0;
+    WorldPos_B111 += (WorldPos_B111 - Center) / 2.0;
+}
+
+void main()
+{
+    for (int i = 0 ; i < 3 ; i++) {
+       tcsVertex[i] = TexCoord_CS_in[i];
+       tevVertex[i] = teVertex[i];
+       tcsNormal[i] = vsNormal[i];
+       tcsColor[i] = vsColor[i];
+    }
+
+    CalcPositions();
+
+    gl_TessLevelOuter[0] = 50;
+    gl_TessLevelOuter[1] = 50;
+    gl_TessLevelOuter[2] = 50;
+    gl_TessLevelOuter[3] = 50;
+    gl_TessLevelInner[0] = 50;
+    gl_TessLevelInner[1] = 50;
+}

avogadro/rendering/mesh_tev.glsl

@@ -0,0 +1,76 @@
+#version 400
+precision highp float;
+
+layout(triangles, equal_spacing, ccw) in;
+
+patch in vec3 WorldPos_B030;
+patch in vec3 WorldPos_B021;
+patch in vec3 WorldPos_B012;
+patch in vec3 WorldPos_B003;
+patch in vec3 WorldPos_B102;
+patch in vec3 WorldPos_B201;
+patch in vec3 WorldPos_B300;
+patch in vec3 WorldPos_B210;
+patch in vec3 WorldPos_B120;
+patch in vec3 WorldPos_B111;
+
+patch in vec2 tcsVertex[3];
+patch in vec3 tcsNormal[3];
+patch in vec3 tevVertex[3];
+patch in vec4 tcsColor[3];
+
+out vec2 teVertex;
+out vec3 teNormal;
+out vec3 WorldPos_FS_in;
+out vec4 teColor;
+
+uniform mat4 modelView;
+uniform mat4 projection;
+
+vec3 interpolate3D(vec3 v0, vec3 v1, vec3 v2)
+{
+    return gl_TessCoord.x * v0 + gl_TessCoord.y * v1 + gl_TessCoord.z * v2;
+}
+
+vec2 interpolate2D(vec2 v0, vec2 v1, vec2 v2)                                                   
+{                                                                                               
+    return gl_TessCoord.x * v0 + gl_TessCoord.y * v1 + gl_TessCoord.z * v2;   
+}                                                                                               
+
+vec4 interpolate4D(vec4 v0, vec4 v1, vec4 v2)                                                   
+{                                                                                               
+    return gl_TessCoord.x * v0 + gl_TessCoord.y * v1 + gl_TessCoord.z * v2;   
+} 
+
+void main()
+{
+    vec2 p0 = tcsVertex[0];
+    vec2 p1 = tcsVertex[1];
+    vec2 p2 = tcsVertex[2];
+
+    vec3 n0 = tcsNormal[0];
+    vec3 n1 = tcsNormal[1];
+    vec3 n2 = tcsNormal[2];
+
+    teVertex = interpolate2D(p0, p1, p2);
+    teNormal = normalize(interpolate3D(tcsNormal[0], tcsNormal[1], tcsNormal[2]));
+    teColor = interpolate4D(tcsColor[0], tcsColor[1], tcsColor[2]); 
+
+    float u = gl_TessCoord.x;                                                                   
+    float v = gl_TessCoord.y;                                                    
+    float w = gl_TessCoord.z;                                      
+
+    float uPow3 = pow(u, 3);                                                                    
+    float vPow3 = pow(v, 3);                                                                    
+    float wPow3 = pow(w, 3);                                                                    
+    float uPow2 = pow(u, 2);                                                                    
+    float vPow2 = pow(v, 2);                                                                    
+    float wPow2 = pow(w, 2); 
+
+    WorldPos_FS_in = WorldPos_B300 * wPow3 + WorldPos_B030 * uPow3 + WorldPos_B003 * vPow3 +                               
+                     WorldPos_B210 * 3.0 * wPow2 * u + WorldPos_B120 * 3.0 * w * uPow2 + WorldPos_B201 * 3.0 * wPow2 * v + 
+                     WorldPos_B021 * 3.0 * uPow2 * v + WorldPos_B102 * 3.0 * w * vPow2 + WorldPos_B012 * 3.0 * u * vPow2 + 
+                     WorldPos_B111 * 6.0 * w * u * v;  
+
+    gl_Position =  projection * vec4(WorldPos_FS_in, 1.0);
+}

avogadro/rendering/mesh_vs.glsl

@@ -1,16 +1,25 @@
-attribute vec4 vertex;
-attribute vec4 color;
-attribute vec3 normal;
+#version 400
+precision highp float;
+
+in vec3 vertex;
+in vec3 normal;
+in vec4 color;
 
 uniform mat4 modelView;
 uniform mat4 projection;
 uniform mat3 normalMatrix;
 
-varying vec3 fnormal;
+out vec3 WorldPos_CS_in;   
+out vec2 TexCoord_CS_in;                                                                     
+out vec3 vsNormal;
+out vec3 teVertex; 
+out vec4 vsColor;
 
 void main()
 {
-  gl_FrontColor = color;
-  gl_Position = projection * modelView * vertex;
-  fnormal = normalize(normalMatrix * normal);
+    vsColor = color;
+    teVertex = vertex;
+    WorldPos_CS_in = (modelView * vec4(vertex, 1.0)).xyz;
+    TexCoord_CS_in = vertex.xy;
+    vsNormal = normalize(normalMatrix * normal);
 }