OpenSubdiv/examples/mayaPtexViewer/shader.glsl
manuelk 10c687ecd5 Release Candidate 1.0 :
- [Feature Adaptive GPU Rendering of Catmull-Clark Surfaces](http://research.microsoft.com/en-us/um/people/cloop/tog2012.pdf).

- New API architecture : we are planning to lock on to this new framework as the basis for backward compatibility, which we will enforce from Release 1.0 onward. Subsequent releases of OpenSubdiv should not break client code.

- DirectX 11 support

- and much more...
2012-12-10 17:15:13 -08:00

455 lines
14 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.
//
#line 57
//--------------------------------------------------------------
// Common
//--------------------------------------------------------------
uniform isamplerBuffer g_ptexIndicesBuffer;
uniform int nonAdaptiveLevel;
vec4 GeneratePatchCoord(vec2 localUV) // for non-adpative
{
ivec2 ptexIndex = texelFetch(g_ptexIndicesBuffer, gl_PrimitiveID).xy;
int faceID = abs(ptexIndex.x);
int lv = 1 << nonAdaptiveLevel;
if (ptexIndex.x < 0) lv >>= 1;
int u = ptexIndex.y >> 16;
int v = (ptexIndex.y & 0xffff);
vec2 uv = localUV;
uv = (uv * vec2(1.0)/lv) + vec2(u, v)/lv;
return vec4(uv.x, uv.y, lv+0.5, faceID+0.5);
}
vec4 PTexLookup(vec4 patchCoord,
sampler2DArray data,
samplerBuffer packings,
isamplerBuffer pages)
{
vec2 uv = patchCoord.xy;
int faceID = int(patchCoord.w);
int page = texelFetch(pages, faceID).x;
vec4 packing = texelFetch(packings, faceID);
vec3 coords = vec3( packing.x + uv.x * packing.z,
packing.y + uv.y * packing.w,
page);
return texture(data, coords);
}
#ifdef USE_PTEX_DISPLACEMENT
#define OSD_DISPLACEMENT_CALLBACK \
output.v.position = \
displacement(output.v.position, \
output.v.normal, \
output.v.patchCoord);
uniform sampler2DArray textureDisplace_Data;
uniform samplerBuffer textureDisplace_Packing;
uniform isamplerBuffer textureDisplace_Pages;
vec4 displacement(vec4 position, vec3 normal, vec4 patchCoord)
{
float disp = PTexLookup(patchCoord,
textureDisplace_Data,
textureDisplace_Packing,
textureDisplace_Pages).x;
return position + vec4(disp * normal, 0);
}
#endif
//--------------------------------------------------------------
// Vertex Shader
//--------------------------------------------------------------
#ifdef VERTEX_SHADER
layout (location=0) in vec3 position;
layout (location=1) in vec3 normal;
out block {
OutputVertex v;
} output;
void main()
{
output.v.position = vec4(position, 1);
output.v.normal = normal;
}
#endif // VERTEX_SHADER
//--------------------------------------------------------------
// Geometry Shader
//--------------------------------------------------------------
#ifdef GEOMETRY_SHADER
#ifdef PRIM_QUAD
layout(lines_adjacency) in;
#ifdef GEOMETRY_OUT_FILL
layout(triangle_strip, max_vertices = 4) out;
#endif
#ifdef GEOMETRY_OUT_LINE
layout(line_strip, max_vertices = 5) out;
#endif
in block {
OutputVertex v;
} input[4];
#endif // PRIM_QUAD
#ifdef PRIM_TRI
layout(triangles) in;
#ifdef GEOMETRY_OUT_FILL
layout(triangle_strip, max_vertices = 3) out;
#endif
#ifdef GEOMETRY_OUT_LINE
layout(line_strip, max_vertices = 4) out;
#endif
in block {
OutputVertex v;
} input[3];
#endif // PRIM_TRI
out block {
OutputVertex v;
} output;
void emit(int index, vec4 position, vec3 normal, vec4 patchCoord)
{
output.v.position = position;
output.v.normal = normal;
output.v.patchCoord = patchCoord;
output.v.tangent = input[index].v.tangent;
gl_Position = ProjectionMatrix * output.v.position;
EmitVertex();
}
void main()
{
gl_PrimitiveID = gl_PrimitiveIDIn;
#ifdef PRIM_QUAD
#ifdef GEOMETRY_OUT_FILL
vec4 patchCoord[4];
vec4 position[4];
vec3 normal[4];
// need to generate patch coord for non-patch quads
patchCoord[0] = GeneratePatchCoord(vec2(0, 0));
patchCoord[1] = GeneratePatchCoord(vec2(1, 0));
patchCoord[2] = GeneratePatchCoord(vec2(1, 1));
patchCoord[3] = GeneratePatchCoord(vec2(0, 1));
#ifdef USE_PTEX_DISPLACEMENT
position[0] = displacement(input[0].v.position, input[0].v.normal, patchCoord[0]);
position[1] = displacement(input[1].v.position, input[1].v.normal, patchCoord[1]);
position[2] = displacement(input[2].v.position, input[2].v.normal, patchCoord[2]);
position[3] = displacement(input[3].v.position, input[3].v.normal, patchCoord[3]);
#else
position[0] = input[0].v.position;
position[1] = input[1].v.position;
position[2] = input[2].v.position;
position[3] = input[3].v.position;
#endif
#ifdef FLAT_NORMALS
// XXX: need to use vec C to get triangle normal.
vec3 A = (position[0] - position[1]).xyz;
vec3 B = (position[3] - position[1]).xyz;
vec3 C = (position[2] - position[1]).xyz;
normal[0] = normalize(cross(B, A));
normal[1] = normal[0];
normal[2] = normal[0];
normal[3] = normal[0];
#else
normal[0] = input[0].v.normal;
normal[1] = input[1].v.normal;
normal[2] = input[2].v.normal;
normal[3] = input[3].v.normal;
#endif
emit(0, position[0], normal[0], patchCoord[0]);
emit(1, position[1], normal[1], patchCoord[1]);
emit(3, position[3], normal[3], patchCoord[3]);
emit(2, position[2], normal[2], patchCoord[2]);
#else // GEOMETRY_OUT_LINE
emit(0, position[0], vec3(0), patchCoord[0]);
emit(1, position[1], vec3(0), patchCoord[1]);
emit(2, position[2], vec3(0), patchCoord[2]);
emit(3, position[3], vec3(0), patchCoord[3]);
emit(0, position[0], vec3(0), patchCoord[0]);
#endif
#endif // PRIM_QUAD
#ifdef PRIM_TRI
vec4 position[3];
vec4 patchCoord[3];
vec3 normal[3];
// patch coords are computed in tessellation shader
patchCoord[0] = input[0].v.patchCoord;
patchCoord[1] = input[1].v.patchCoord;
patchCoord[2] = input[2].v.patchCoord;
#ifdef USE_PTEX_DISPLACEMENT
position[0] = displacement(input[0].v.position, input[0].v.normal, patchCoord[0]);
position[1] = displacement(input[1].v.position, input[1].v.normal, patchCoord[1]);
position[2] = displacement(input[2].v.position, input[2].v.normal, patchCoord[2]);
#else
position[0] = input[0].v.position;
position[1] = input[1].v.position;
position[2] = input[2].v.position;
#endif
#ifdef FLAT_NORMALS // emit flat normals for displaced surface
vec3 A = (position[0] - position[1]).xyz;
vec3 B = (position[2] - position[1]).xyz;
normal[0] = normalize(cross(B, A));
normal[1] = normal[0];
normal[2] = normal[0];
#else
normal[0] = input[0].v.normal;
normal[1] = input[1].v.normal;
normal[2] = input[2].v.normal;
#endif
emit(0, position[0], normal[0], patchCoord[0]);
emit(1, position[1], normal[1], patchCoord[1]);
emit(2, position[2], normal[2], patchCoord[2]);
#ifdef GEOMETRY_OUT_LINE
emit(0, position[0], normal[0], patchCoord[0]);
#endif //GEOMETRY_OUT_LINE
#endif // PRIM_TRI
EndPrimitive();
}
#endif // GEOMETRY_SHADER
//--------------------------------------------------------------
// Fragment Shader
//--------------------------------------------------------------
#ifdef FRAGMENT_SHADER
in block {
OutputVertex v;
} input;
uniform int ptexFaceOffset;
#ifdef USE_PTEX_COLOR
uniform sampler2DArray textureImage_Data;
uniform samplerBuffer textureImage_Packing;
uniform isamplerBuffer textureImage_Pages;
#endif
#ifdef USE_PTEX_OCCLUSION
uniform sampler2DArray textureOcclusion_Data;
uniform samplerBuffer textureOcclusion_Packing;
uniform isamplerBuffer textureOcclusion_Pages;
#endif
#if USE_PTEX_NORMAL
uniform sampler2DArray textureDisplace_Data;
uniform samplerBuffer textureDisplace_Packing;
uniform isamplerBuffer textureDisplace_Pages;
vec3
perturbNormalFromDisplacement(vec3 position, vec3 normal, vec4 patchCoord)
{
// by Morten S. Mikkelsen
// http://jbit.net/~sparky/sfgrad_bump/mm_sfgrad_bump.pdf
// slightly modified for ptex guttering
vec3 vSigmaS = dFdx(position);
vec3 vSigmaT = dFdy(position);
vec3 vN = normal;
vec3 vR1 = cross(vSigmaT, vN);
vec3 vR2 = cross(vN, vSigmaS);
float fDet = dot(vSigmaS, vR1);
#if 0
// not work well with ptex
float dBs = dFdx(disp);
float dBt = dFdy(disp);
#else
vec2 texDx = dFdx(patchCoord.xy);
vec2 texDy = dFdy(patchCoord.xy);
// limit forward differencing to the width of ptex gutter
const float resolution = 128.0;
float d = min(1, (0.5/resolution)/max(length(texDx), length(texDy)));
vec4 STll = patchCoord;
vec4 STlr = patchCoord + d * vec4(texDx.x, texDx.y, 0, 0);
vec4 STul = patchCoord + d * vec4(texDy.x, texDy.y, 0, 0);
float Hll = PTexLookup(STll, textureDisplace_Data, textureDisplace_Packing, textureDisplace_Pages).x;
float Hlr = PTexLookup(STlr, textureDisplace_Data, textureDisplace_Packing, textureDisplace_Pages).x;
float Hul = PTexLookup(STul, textureDisplace_Data, textureDisplace_Packing, textureDisplace_Pages).x;
float dBs = (Hlr - Hll)/d;
float dBt = (Hul - Hll)/d;
#endif
vec3 vSurfGrad = sign(fDet) * (dBs * vR1 + dBt * vR2);
return normalize(abs(fDet) * vN - vSurfGrad);
}
#endif // USE_PTEX_NORMAL
uniform sampler2D diffuseEnvironmentMap;
uniform sampler2D specularEnvironmentMap;
#define NUM_LIGHTS 1
struct LightSource {
vec4 position;
vec4 diffuse;
vec4 ambient;
vec4 specular;
};
layout(std140) uniform Lighting {
LightSource lightSource[NUM_LIGHTS];
};
uniform vec4 diffuseColor;
uniform vec4 ambientColor;
uniform vec4 specularColor;
uniform vec3 eyePositionInWorld;
uniform float fresnelBias;
uniform float fresnelScale;
uniform float fresnelPower;
vec4 getEnvironment(sampler2D sampler, vec3 dir)
{
return texture(sampler, vec2((atan(dir.x,dir.z)/3.1415926+1)*0.5, (1-dir.y)*0.5));
}
void
main()
{
#ifdef USE_PTEX_COLOR
vec4 texColor = PTexLookup(input.v.patchCoord,
textureImage_Data,
textureImage_Packing,
textureImage_Pages);
#else
vec4 texColor = vec4(1);
#endif
#if USE_PTEX_NORMAL
vec3 objN = perturbNormalFromDisplacement(input.v.position.xyz,
input.v.normal,
input.v.patchCoord);
#else
vec3 objN = input.v.normal;
#endif
#ifdef USE_PTEX_OCCLUSION
float occ = PTexLookup(input.v.patchCoord,
textureOcclusion_Data,
textureOcclusion_Packing,
textureOcclusion_Pages).x;
#else
float occ = 0.0;
#endif
vec4 a = ambientColor;
#ifdef USE_DIFFUSE_ENV_MAP
vec4 d = getEnvironment(diffuseEnvironmentMap, objN) * 1.4;
#else
vec4 d = vec4(1);
#endif
vec3 eye = normalize(input.v.position.xyz - eyePositionInWorld);
#ifdef USE_SPECULAR_ENV_MAP
vec3 reflect = reflect(eye, objN);
vec4 s = getEnvironment(specularEnvironmentMap, reflect);
#else
vec4 s = vec4(1);
#endif
float fresnel = fresnelBias + fresnelScale * pow(1.0+dot(objN,eye), fresnelPower);
a *= (1.0-occ);
d *= (1.0-occ)*diffuseColor;
s *= (1.0-pow(occ, 0.2)) * specularColor * fresnel;
gl_FragColor = (a + d) * texColor + s;
gl_FragColor = pow(gl_FragColor, vec4(0.4545));
}
#endif // FRAGMENT_SHADER