OpenSubdiv/examples/facePartition/shader.glsl
Takahito Tejima ee061291b7 Interleaved buffer support in OsdCompute. Removed OsdVertexDescriptor and replaced with OsdVertexBufferDescriptor.
All kernels take offset/length/stride to apply subdivision partially in each vertex elements.

Also the offset can be used for client-based VBO aggregation, without modifying index buffers.
This is useful for topology sharing, in conjunction with glDrawElementsBaseVertex etc.
However, gregory patch shader fetches vertex buffer via texture buffer, which index should also
be offsetted too. Although gl_BaseVertexARB extension should be able to do that job, it's a
relatively new extension. So we use OsdBaseVertex() call to mitigate the compatibility
issue as clients can provide it in their way at least for the time being.
2014-05-09 15:44:52 -07:00

332 lines
7.9 KiB
GLSL

//
// Copyright 2014 Pixar
//
// Licensed under the Apache License, Version 2.0 (the "Apache License")
// with the following modification; you may not use this file except in
// compliance with the Apache License and the following modification to it:
// Section 6. Trademarks. is 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 to comply with Section 4(c) of
// the License and to reproduce the content of the NOTICE file.
//
// You may obtain a copy of the Apache License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the Apache License with the above modification is
// distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied. See the Apache License for the specific
// language governing permissions and limitations under the Apache License.
//
//--------------------------------------------------------------
// Uniforms / Uniform Blocks
//--------------------------------------------------------------
layout(std140) uniform Transform {
mat4 ModelViewMatrix;
mat4 ProjectionMatrix;
mat4 ModelViewProjectionMatrix;
};
layout(std140) uniform Tessellation {
float TessLevel;
};
uniform int GregoryQuadOffsetBase;
uniform int PrimitiveIdBase;
//--------------------------------------------------------------
// Osd external functions
//--------------------------------------------------------------
mat4 OsdModelViewMatrix()
{
return ModelViewMatrix;
}
mat4 OsdProjectionMatrix()
{
return ProjectionMatrix;
}
mat4 OsdModelViewProjectionMatrix()
{
return ModelViewProjectionMatrix;
}
float OsdTessLevel()
{
return TessLevel;
}
int OsdGregoryQuadOffsetBase()
{
return GregoryQuadOffsetBase;
}
int OsdPrimitiveIdBase()
{
return PrimitiveIdBase;
}
int OsdBaseVertex()
{
return 0;
}
//--------------------------------------------------------------
// Vertex Shader
//--------------------------------------------------------------
#ifdef VERTEX_SHADER
layout (location=0) in vec4 position;
out block {
OutputVertex v;
} outpt;
void main()
{
outpt.v.position = ModelViewMatrix * position;
}
#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 block {
OutputVertex v;
} inpt[EDGE_VERTS];
out block {
OutputVertex v;
noperspective out vec4 edgeDistance;
} outpt;
void emit(int index, vec3 normal)
{
outpt.v.position = inpt[index].v.position;
#ifdef SMOOTH_NORMALS
outpt.v.normal = inpt[index].v.normal;
#else
outpt.v.normal = normal;
#endif
gl_Position = ProjectionMatrix * inpt[index].v.position;
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])
{
outpt.edgeDistance[0] =
edgeDistance(edgeVerts[index], edgeVerts[0], edgeVerts[1]);
outpt.edgeDistance[1] =
edgeDistance(edgeVerts[index], edgeVerts[1], edgeVerts[2]);
#ifdef PRIM_TRI
outpt.edgeDistance[2] =
edgeDistance(edgeVerts[index], edgeVerts[2], edgeVerts[0]);
#endif
#ifdef PRIM_QUAD
outpt.edgeDistance[2] =
edgeDistance(edgeVerts[index], edgeVerts[2], edgeVerts[3]);
outpt.edgeDistance[3] =
edgeDistance(edgeVerts[index], edgeVerts[3], edgeVerts[0]);
#endif
emit(index, normal);
}
#endif
void main()
{
gl_PrimitiveID = gl_PrimitiveIDIn;
#ifdef PRIM_QUAD
vec3 A = (inpt[0].v.position - inpt[1].v.position).xyz;
vec3 B = (inpt[3].v.position - inpt[1].v.position).xyz;
vec3 C = (inpt[2].v.position - inpt[1].v.position).xyz;
vec3 n0 = normalize(cross(B, A));
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
vec4 edgeVerts[EDGE_VERTS];
edgeVerts[0] = ProjectionMatrix * inpt[0].v.position;
edgeVerts[1] = ProjectionMatrix * inpt[1].v.position;
edgeVerts[2] = ProjectionMatrix * inpt[2].v.position;
edgeVerts[3] = ProjectionMatrix * inpt[3].v.position;
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 = (inpt[1].v.position - inpt[0].v.position).xyz;
vec3 B = (inpt[2].v.position - inpt[0].v.position).xyz;
vec3 n0 = normalize(cross(B, A));
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
vec4 edgeVerts[EDGE_VERTS];
edgeVerts[0] = ProjectionMatrix * inpt[0].v.position;
edgeVerts[1] = ProjectionMatrix * inpt[1].v.position;
edgeVerts[2] = ProjectionMatrix * inpt[2].v.position;
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 block {
OutputVertex v;
noperspective in vec4 edgeDistance;
} inpt;
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;
}
vec4
edgeColor(vec4 Cfill, vec4 edgeDistance)
{
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
#ifdef PRIM_TRI
float d =
min(inpt.edgeDistance[0], min(inpt.edgeDistance[1], inpt.edgeDistance[2]));
#endif
#ifdef PRIM_QUAD
float d =
min(min(inpt.edgeDistance[0], inpt.edgeDistance[1]),
min(inpt.edgeDistance[2], inpt.edgeDistance[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 ? inpt.v.normal : -inpt.v.normal);
vec4 color = diffuseColor;
vec4 Cf = lighting(color, inpt.v.position.xyz, N);
#if defined(GEOMETRY_OUT_WIRE) || defined(GEOMETRY_OUT_LINE)
Cf = edgeColor(Cf, inpt.edgeDistance);
#endif
outColor = Cf;
}
#endif
#endif