OpenSubdiv/examples/mayaPtexViewer/shader.glsl
Takahito Tejima 51a45b598d Updating EULA
2013-07-18 14:19:50 -07:00

419 lines
12 KiB
GLSL

//
// Copyright 2013 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License
// and the following modification to it: Section 6 Trademarks.
// deleted and replaced with:
//
// 6. Trademarks. This License does not grant permission to use the
// trade names, trademarks, service marks, or product names of the
// Licensor and its affiliates, except as required for reproducing
// the content of the NOTICE file.
//
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
// either express or implied. See the License for the specific
// language governing permissions and limitations under the
// License.
//
#line 57
//--------------------------------------------------------------
// Common
//--------------------------------------------------------------
vec4 GeneratePatchCoord(vec2 localUV) // for non-adpative
{
ivec2 ptexIndex = texelFetch(OsdPatchParamBuffer, gl_PrimitiveID).xy;
int faceID = ptexIndex.x;
int lv = 1 << ((ptexIndex.y & 0xf) - ((ptexIndex.y >> 4) & 1));
int u = (ptexIndex.y >> 17) & 0x3ff;
int v = (ptexIndex.y >> 7) & 0x3ff;
vec2 uv = localUV;
uv = (uv * vec2(1.0)/lv) + vec2(u, v)/lv;
}
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 \
outpt.v.position = \
displacement(outpt.v.position, \
outpt.v.normal, \
outpt.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;
} outpt;
void main()
{
outpt.v.position = vec4(position, 1);
outpt.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;
} inpt[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;
} inpt[3];
#endif // PRIM_TRI
out block {
OutputVertex v;
} outpt;
void emit(int index, vec4 position, vec3 normal, vec4 patchCoord)
{
outpt.v.position = position;
outpt.v.normal = normal;
outpt.v.patchCoord = patchCoord;
outpt.v.tangent = inpt[index].v.tangent;
gl_Position = ProjectionMatrix * outpt.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(inpt[0].v.position, inpt[0].v.normal, patchCoord[0]);
position[1] = displacement(inpt[1].v.position, inpt[1].v.normal, patchCoord[1]);
position[2] = displacement(inpt[2].v.position, inpt[2].v.normal, patchCoord[2]);
position[3] = displacement(inpt[3].v.position, inpt[3].v.normal, patchCoord[3]);
#else
position[0] = inpt[0].v.position;
position[1] = inpt[1].v.position;
position[2] = inpt[2].v.position;
position[3] = inpt[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] = inpt[0].v.normal;
normal[1] = inpt[1].v.normal;
normal[2] = inpt[2].v.normal;
normal[3] = inpt[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] = inpt[0].v.patchCoord;
patchCoord[1] = inpt[1].v.patchCoord;
patchCoord[2] = inpt[2].v.patchCoord;
#ifdef USE_PTEX_DISPLACEMENT
position[0] = displacement(inpt[0].v.position, inpt[0].v.normal, patchCoord[0]);
position[1] = displacement(inpt[1].v.position, inpt[1].v.normal, patchCoord[1]);
position[2] = displacement(inpt[2].v.position, inpt[2].v.normal, patchCoord[2]);
#else
position[0] = inpt[0].v.position;
position[1] = inpt[1].v.position;
position[2] = inpt[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] = inpt[0].v.normal;
normal[1] = inpt[1].v.normal;
normal[2] = inpt[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;
} inpt;
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(inpt.v.patchCoord,
textureImage_Data,
textureImage_Packing,
textureImage_Pages);
#else
vec4 texColor = vec4(1);
#endif
#if USE_PTEX_NORMAL
vec3 objN = perturbNormalFromDisplacement(inpt.v.position.xyz,
inpt.v.normal,
inpt.v.patchCoord);
#else
vec3 objN = inpt.v.normal;
#endif
#ifdef USE_PTEX_OCCLUSION
float occ = PTexLookup(inpt.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(inpt.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