OpenSubdiv/examples/glViewer/shader_gl3.glsl
2013-06-27 14:05:24 -07:00

350 lines
9.2 KiB
GLSL

//
// Copyright (C) Pixar. All rights reserved.
//
// This license governs use of the accompanying software. If you
// use the software, you accept this license. If you do not accept
// the license, do not use the software.
//
// 1. Definitions
// The terms "reproduce," "reproduction," "derivative works," and
// "distribution" have the same meaning here as under U.S.
// copyright law. A "contribution" is the original software, or
// any additions or changes to the software.
// A "contributor" is any person or entity that distributes its
// contribution under this license.
// "Licensed patents" are a contributor's patent claims that read
// directly on its contribution.
//
// 2. Grant of Rights
// (A) Copyright Grant- Subject to the terms of this license,
// including the license conditions and limitations in section 3,
// each contributor grants you a non-exclusive, worldwide,
// royalty-free copyright license to reproduce its contribution,
// prepare derivative works of its contribution, and distribute
// its contribution or any derivative works that you create.
// (B) Patent Grant- Subject to the terms of this license,
// including the license conditions and limitations in section 3,
// each contributor grants you a non-exclusive, worldwide,
// royalty-free license under its licensed patents to make, have
// made, use, sell, offer for sale, import, and/or otherwise
// dispose of its contribution in the software or derivative works
// of the contribution in the software.
//
// 3. Conditions and Limitations
// (A) No Trademark License- This license does not grant you
// rights to use any contributor's name, logo, or trademarks.
// (B) If you bring a patent claim against any contributor over
// patents that you claim are infringed by the software, your
// patent license from such contributor to the software ends
// automatically.
// (C) If you distribute any portion of the software, you must
// retain all copyright, patent, trademark, and attribution
// notices that are present in the software.
// (D) If you distribute any portion of the software in source
// code form, you may do so only under this license by including a
// complete copy of this license with your distribution. If you
// distribute any portion of the software in compiled or object
// code form, you may only do so under a license that complies
// with this license.
// (E) The software is licensed "as-is." You bear the risk of
// using it. The contributors give no express warranties,
// guarantees or conditions. You may have additional consumer
// rights under your local laws which this license cannot change.
// To the extent permitted under your local laws, the contributors
// exclude the implied warranties of merchantability, fitness for
// a particular purpose and non-infringement.
//
layout(std140) uniform Transform {
mat4 ModelViewMatrix;
mat4 ProjectionMatrix;
mat4 ModelViewProjectionMatrix;
mat4 ModelViewInverseMatrix;
};
//--------------------------------------------------------------
// Vertex Shader
//--------------------------------------------------------------
#ifdef VERTEX_SHADER
layout (location=0) in vec4 position;
out vec4 vPosition;
#ifdef VARYING_COLOR
layout (location=1) in vec3 color;
out vec3 vColor;
#endif
void main()
{
vPosition = ModelViewMatrix * position;
#ifdef VARYING_COLOR
vColor = color;
#endif
}
#endif
//--------------------------------------------------------------
// Geometry Shader
//--------------------------------------------------------------
#ifdef GEOMETRY_SHADER
#ifdef PRIM_QUAD
layout(lines_adjacency) in;
#define EDGE_VERTS 4
#endif // PRIM_QUAD
#ifdef PRIM_TRI
layout(triangles) in;
#define EDGE_VERTS 3
#endif // PRIM_TRI
layout(triangle_strip, max_vertices = EDGE_VERTS) out;
in vec4 vPosition[EDGE_VERTS];
#ifdef VARYING_COLOR
in vec3 vColor[EDGE_VERTS];
#endif
out vec4 gPosition;
out vec3 gNormal;
noperspective out vec4 gEdgeDistance;
#ifdef VARYING_COLOR
out vec3 gColor;
#endif
void emit(int index, vec3 normal)
{
gPosition = vPosition[index];
#ifdef SMOOTH_NORMALS
gNormal = vNormal[index];
#else
gNormal = normal;
#endif
#ifdef VARYING_COLOR
gColor = vColor[index];
#endif
gl_Position = ProjectionMatrix * vPosition[index];
EmitVertex();
}
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
const float VIEWPORT_SCALE = 1024.0; // XXXdyu
float edgeDistance(vec4 p, vec4 p0, vec4 p1)
{
return VIEWPORT_SCALE *
abs((p.x - p0.x) * (p1.y - p0.y) -
(p.y - p0.y) * (p1.x - p0.x)) / length(p1.xy - p0.xy);
}
void emit(int index, vec3 normal, vec4 edgeVerts[EDGE_VERTS])
{
gEdgeDistance[0] =
edgeDistance(edgeVerts[index], edgeVerts[0], edgeVerts[1]);
gEdgeDistance[1] =
edgeDistance(edgeVerts[index], edgeVerts[1], edgeVerts[2]);
#ifdef PRIM_TRI
gEdgeDistance[2] =
edgeDistance(edgeVerts[index], edgeVerts[2], edgeVerts[0]);
#endif
#ifdef PRIM_QUAD
gEdgeDistance[2] =
edgeDistance(edgeVerts[index], edgeVerts[2], edgeVerts[3]);
gEdgeDistance[3] =
edgeDistance(edgeVerts[index], edgeVerts[3], edgeVerts[0]);
#endif
emit(index, normal);
}
#endif
void main()
{
gl_PrimitiveID = gl_PrimitiveIDIn;
#ifdef PRIM_POINT
emit(0, vec3(0));
#endif
#ifdef PRIM_QUAD
vec3 A = (vPosition[0] - vPosition[1]).xyz;
vec3 B = (vPosition[3] - vPosition[1]).xyz;
vec3 C = (vPosition[2] - vPosition[1]).xyz;
vec3 n0 = normalize(cross(B, A));
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
vec4 edgeVerts[EDGE_VERTS];
edgeVerts[0] = ProjectionMatrix * vPosition[0];
edgeVerts[1] = ProjectionMatrix * vPosition[1];
edgeVerts[2] = ProjectionMatrix * vPosition[2];
edgeVerts[3] = ProjectionMatrix * vPosition[3];
edgeVerts[0].xy /= edgeVerts[0].w;
edgeVerts[1].xy /= edgeVerts[1].w;
edgeVerts[2].xy /= edgeVerts[2].w;
edgeVerts[3].xy /= edgeVerts[3].w;
emit(0, n0, edgeVerts);
emit(1, n0, edgeVerts);
emit(3, n0, edgeVerts);
emit(2, n0, edgeVerts);
#else
emit(0, n0);
emit(1, n0);
emit(3, n0);
emit(2, n0);
#endif
#endif // PRIM_QUAD
#ifdef PRIM_TRI
vec3 A = (vPosition[1] - vPosition[0]).xyz;
vec3 B = (vPosition[2] - vPosition[0]).xyz;
vec3 n0 = normalize(cross(B, A));
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
vec4 edgeVerts[EDGE_VERTS];
edgeVerts[0] = ProjectionMatrix * vPosition[0];
edgeVerts[1] = ProjectionMatrix * vPosition[1];
edgeVerts[2] = ProjectionMatrix * vPosition[2];
edgeVerts[0].xy /= edgeVerts[0].w;
edgeVerts[1].xy /= edgeVerts[1].w;
edgeVerts[2].xy /= edgeVerts[2].w;
emit(0, n0, edgeVerts);
emit(1, n0, edgeVerts);
emit(2, n0, edgeVerts);
#else
emit(0, n0);
emit(1, n0);
emit(2, n0);
#endif
#endif // PRIM_TRI
EndPrimitive();
}
#endif
//--------------------------------------------------------------
// Fragment Shader
//--------------------------------------------------------------
#ifdef FRAGMENT_SHADER
in vec4 gPosition;
in vec3 gNormal;
noperspective in vec4 gEdgeDistance;
#ifdef VARYING_COLOR
in vec3 gColor;
#endif
out vec4 outColor;
#define NUM_LIGHTS 2
struct LightSource {
vec4 position;
vec4 ambient;
vec4 diffuse;
vec4 specular;
};
layout(std140) uniform Lighting {
LightSource lightSource[NUM_LIGHTS];
};
uniform vec4 diffuseColor = vec4(1);
uniform vec4 ambientColor = vec4(1);
vec4
lighting(vec4 diffuse, vec3 Peye, vec3 Neye)
{
vec4 color = vec4(0);
for (int i = 0; i < NUM_LIGHTS; ++i) {
vec4 Plight = lightSource[i].position;
vec3 l = (Plight.w == 0.0)
? normalize(Plight.xyz) : normalize(Plight.xyz - Peye);
vec3 n = normalize(Neye);
vec3 h = normalize(l + vec3(0,0,1)); // directional viewer
float d = max(0.0, dot(n, l));
float s = pow(max(0.0, dot(n, h)), 500.0f);
color += lightSource[i].ambient * ambientColor
+ d * lightSource[i].diffuse * diffuse
+ s * lightSource[i].specular;
}
color.a = 1;
return color;
}
#ifdef PRIM_POINT
uniform vec4 fragColor;
void
main()
{
outColor = fragColor;
}
#endif
vec4
edgeColor(vec4 Cfill, vec4 edgeDistance)
{
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
#ifdef PRIM_TRI
float d =
min(gEdgeDistance[0], min(gEdgeDistance[1], gEdgeDistance[2]));
#endif
#ifdef PRIM_QUAD
float d =
min(min(gEdgeDistance[0], gEdgeDistance[1]),
min(gEdgeDistance[2], gEdgeDistance[3]));
#endif
vec4 Cedge = vec4(1.0, 1.0, 0.0, 1.0);
float p = exp2(-2 * d * d);
#if defined(GEOMETRY_OUT_WIRE)
if (p < 0.25) discard;
#endif
Cfill.rgb = mix(Cfill.rgb, Cedge.rgb, p);
#endif
return Cfill;
}
#if defined(PRIM_QUAD) || defined(PRIM_TRI)
void
main()
{
vec3 N = (gl_FrontFacing ? gNormal : -gNormal);
#ifdef VARYING_COLOR
vec4 color = vec4(gColor, 1);
#else
vec4 color = diffuseColor;
#endif
vec4 Cf = lighting(color, gPosition.xyz, N);
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
Cf = edgeColor(Cf, gEdgeDistance);
#endif
outColor = Cf;
}
#endif
#endif