OpenSubdiv/opensubdiv/osd/glslPatchBSpline.glsl
Takahito Tejima f7f2ca2581 Move uniform block definitions out of osd common shader into client shader.
Important notice: all client shader code must have following functions and compose them to osd intrinsic shaders (vertex/tessEval/tessControl)

mat4 OsdModelViewMatrix()
mat4 OsdProjectionMatrix()
mat4 OsdModelViewProjectionMatrix()
float OsdTessLevel()
int OsdGreogryQuadOffsetBase()
int OsdPrimitiveIdBase()

We probably should write a utility class for basic binding of them, to make client code simpler.
2013-12-03 15:59:38 -08:00

357 lines
9.9 KiB
GLSL

//
// Copyright 2013 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.
//
//----------------------------------------------------------
// Patches.TessVertexBSpline
//----------------------------------------------------------
#ifdef OSD_PATCH_VERTEX_BSPLINE_SHADER
layout(location = 0) in vec4 position;
OSD_USER_VARYING_ATTRIBUTE_DECLARE
out block {
ControlVertex v;
OSD_USER_VARYING_DECLARE
} outpt;
void main()
{
outpt.v.position = OsdModelViewMatrix() * position;
OSD_PATCH_CULL_COMPUTE_CLIPFLAGS(position);
OSD_USER_VARYING_PER_VERTEX();
}
#endif
//----------------------------------------------------------
// Patches.TessControlBSpline
//----------------------------------------------------------
#ifdef OSD_PATCH_TESS_CONTROL_BSPLINE_SHADER
// Regular
uniform mat4 Q = mat4(
1.f/6.f, 4.f/6.f, 1.f/6.f, 0.f,
0.f, 4.f/6.f, 2.f/6.f, 0.f,
0.f, 2.f/6.f, 4.f/6.f, 0.f,
0.f, 1.f/6.f, 4.f/6.f, 1.f/6.f
);
// Boundary / Corner
uniform mat4x3 B = mat4x3(
1.f, 0.f, 0.f,
4.f/6.f, 2.f/6.f, 0.f,
2.f/6.f, 4.f/6.f, 0.f,
1.f/6.f, 4.f/6.f, 1.f/6.f
);
layout(vertices = 16) out;
in block {
ControlVertex v;
OSD_USER_VARYING_DECLARE
} inpt[];
out block {
ControlVertex v;
OSD_USER_VARYING_DECLARE
} outpt[];
#define ID gl_InvocationID
void main()
{
int i = ID%4;
int j = ID/4;
#if defined OSD_PATCH_BOUNDARY
vec3 H[3];
for (int l=0; l<3; ++l) {
H[l] = vec3(0,0,0);
for (int k=0; k<4; ++k) {
H[l] += Q[i][k] * inpt[l*4 + k].v.position.xyz;
}
}
vec3 pos = vec3(0,0,0);
for (int k=0; k<3; ++k) {
pos += B[j][k]*H[k];
}
#elif defined OSD_PATCH_CORNER
vec3 H[3];
for (int l=0; l<3; ++l) {
H[l] = vec3(0,0,0);
for (int k=0; k<3; ++k) {
H[l] += B[3-i][2-k] * inpt[l*3 + k].v.position.xyz;
}
}
vec3 pos = vec3(0,0,0);
for (int k=0; k<3; ++k) {
pos += B[j][k]*H[k];
}
#else // not OSD_PATCH_BOUNDARY, not OSD_PATCH_CORNER
vec3 H[4];
for (int l=0; l<4; ++l) {
H[l] = vec3(0,0,0);
for (int k=0; k<4; ++k) {
H[l] += Q[i][k] * inpt[l*4 + k].v.position.xyz;
}
}
vec3 pos = vec3(0,0,0);
for (int k=0; k<4; ++k) {
pos += Q[j][k]*H[k];
}
#endif
outpt[ID].v.position = vec4(pos, 1.0);
#if defined OSD_PATCH_BOUNDARY
const int p[16] = int[]( 0, 1, 2, 3, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 );
#elif defined OSD_PATCH_CORNER
const int p[16] = int[]( 0, 1, 2, 2, 0, 1, 2, 2, 3, 4, 5, 5, 6, 7, 8, 8 );
#else
const int p[16] = int[]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 );
#endif
#if OSD_TRANSITION_ROTATE == 0
const int r[16] = int[]( 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 );
#elif OSD_TRANSITION_ROTATE == 1
const int r[16] = int[]( 12, 8, 4, 0, 13, 9, 5, 1, 14, 10, 6, 2, 15, 11, 7, 3 );
#elif OSD_TRANSITION_ROTATE == 2
const int r[16] = int[]( 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0 );
#elif OSD_TRANSITION_ROTATE == 3
const int r[16] = int[]( 3, 7, 11, 15, 2, 6, 10, 14, 1, 5, 9, 13, 0, 4, 8, 12 );
#endif
OSD_USER_VARYING_PER_CONTROL_POINT(ID, p[r[ID]]);
int patchLevel = GetPatchLevel();
// +0.5 to avoid interpolation error of integer value
outpt[ID].v.patchCoord = vec4(0, 0,
patchLevel+0.5,
GetPrimitiveID()+0.5);
OSD_COMPUTE_PTEX_COORD_TESSCONTROL_SHADER;
if (ID == 0) {
OSD_PATCH_CULL(OSD_PATCH_INPUT_SIZE);
#ifdef OSD_PATCH_TRANSITION
vec3 cp[OSD_PATCH_INPUT_SIZE];
for(int k = 0; k < OSD_PATCH_INPUT_SIZE; ++k) cp[k] = inpt[k].v.position.xyz;
SetTransitionTessLevels(cp, patchLevel);
#else
#if defined OSD_PATCH_BOUNDARY
const int p[4] = int[]( 1, 2, 5, 6 );
#elif defined OSD_PATCH_CORNER
const int p[4] = int[]( 1, 2, 4, 5 );
#else
const int p[4] = int[]( 5, 6, 9, 10 );
#endif
#ifdef OSD_ENABLE_SCREENSPACE_TESSELLATION
gl_TessLevelOuter[0] = TessAdaptive(inpt[p[0]].v.position.xyz, inpt[p[2]].v.position.xyz);
gl_TessLevelOuter[1] = TessAdaptive(inpt[p[0]].v.position.xyz, inpt[p[1]].v.position.xyz);
gl_TessLevelOuter[2] = TessAdaptive(inpt[p[1]].v.position.xyz, inpt[p[3]].v.position.xyz);
gl_TessLevelOuter[3] = TessAdaptive(inpt[p[2]].v.position.xyz, inpt[p[3]].v.position.xyz);
gl_TessLevelInner[0] = max(gl_TessLevelOuter[1], gl_TessLevelOuter[3]);
gl_TessLevelInner[1] = max(gl_TessLevelOuter[0], gl_TessLevelOuter[2]);
#else
gl_TessLevelInner[0] = GetTessLevel(patchLevel);
gl_TessLevelInner[1] = GetTessLevel(patchLevel);
gl_TessLevelOuter[0] = GetTessLevel(patchLevel);
gl_TessLevelOuter[1] = GetTessLevel(patchLevel);
gl_TessLevelOuter[2] = GetTessLevel(patchLevel);
gl_TessLevelOuter[3] = GetTessLevel(patchLevel);
#endif
#endif
}
}
#endif
//----------------------------------------------------------
// Patches.TessEvalBSpline
//----------------------------------------------------------
#ifdef OSD_PATCH_TESS_EVAL_BSPLINE_SHADER
#ifdef OSD_TRANSITION_TRIANGLE_SUBPATCH
layout(triangles) in;
#else
layout(quads) in;
#endif
#if defined OSD_FRACTIONAL_ODD_SPACING
layout(fractional_odd_spacing) in;
#elif defined OSD_FRACTIONAL_EVEN_SPACING
layout(fractional_even_spacing) in;
#endif
in block {
ControlVertex v;
OSD_USER_VARYING_DECLARE
} inpt[];
out block {
OutputVertex v;
OSD_USER_VARYING_DECLARE
} outpt;
void main()
{
#ifdef OSD_PATCH_TRANSITION
vec2 UV = GetTransitionSubpatchUV();
#else
vec2 UV = gl_TessCoord.xy;
#endif
#ifdef OSD_COMPUTE_NORMAL_DERIVATIVES
float B[4], D[4], C[4];
vec3 BUCP[4], DUCP[4], CUCP[4];
Univar4x4(UV.x, B, D, C);
#else
float B[4], D[4];
vec3 BUCP[4], DUCP[4];
Univar4x4(UV.x, B, D);
#endif
for (int i=0; i<4; ++i) {
BUCP[i] = vec3(0);
DUCP[i] = vec3(0);
#ifdef OSD_COMPUTE_NORMAL_DERIVATIVES
CUCP[i] = vec3(0);
#endif
for (int j=0; j<4; ++j) {
#if OSD_TRANSITION_ROTATE == 1
vec3 A = inpt[4*(3-j) + i].v.position.xyz;
#elif OSD_TRANSITION_ROTATE == 2
vec3 A = inpt[4*(3-i) + (3-j)].v.position.xyz;
#elif OSD_TRANSITION_ROTATE == 3
vec3 A = inpt[4*j + (3-i)].v.position.xyz;
#else // OSD_TRANSITION_ROTATE == 0, or non-transition patch
vec3 A = inpt[4*i + j].v.position.xyz;
#endif
BUCP[i] += A * B[j];
DUCP[i] += A * D[j];
#ifdef OSD_COMPUTE_NORMAL_DERIVATIVES
CUCP[i] += A * C[j];
#endif
}
}
vec3 WorldPos = vec3(0);
vec3 Tangent = vec3(0);
vec3 BiTangent = vec3(0);
#ifdef OSD_COMPUTE_NORMAL_DERIVATIVES
// used for weingarten term
Univar4x4(UV.y, B, D, C);
vec3 dUU = vec3(0);
vec3 dVV = vec3(0);
vec3 dUV = vec3(0);
for (int k=0; k<4; ++k) {
WorldPos += B[k] * BUCP[k];
Tangent += B[k] * DUCP[k];
BiTangent += D[k] * BUCP[k];
dUU += B[k] * CUCP[k];
dVV += C[k] * BUCP[k];
dUV += D[k] * DUCP[k];
}
int level = int(inpt[0].v.ptexInfo.z);
Tangent *= 3 * level;
BiTangent *= 3 * level;
dUU *= 6 * level;
dVV *= 6 * level;
dUV *= 9 * level;
vec3 n = cross(Tangent, BiTangent);
vec3 normal = normalize(n);
float E = dot(Tangent, Tangent);
float F = dot(Tangent, BiTangent);
float G = dot(BiTangent, BiTangent);
float e = dot(normal, dUU);
float f = dot(normal, dUV);
float g = dot(normal, dVV);
vec3 Nu = (f*F-e*G)/(E*G-F*F) * Tangent + (e*F-f*E)/(E*G-F*F) * BiTangent;
vec3 Nv = (g*F-f*G)/(E*G-F*F) * Tangent + (f*F-g*E)/(E*G-F*F) * BiTangent;
Nu = Nu/length(n) - n * (dot(Nu,n)/pow(dot(n,n), 1.5));
Nv = Nv/length(n) - n * (dot(Nv,n)/pow(dot(n,n), 1.5));
OSD_COMPUTE_PTEX_COMPATIBLE_DERIVATIVES(OSD_TRANSITION_ROTATE);
#else
Univar4x4(UV.y, B, D);
for (int k=0; k<4; ++k) {
WorldPos += B[k] * BUCP[k];
Tangent += B[k] * DUCP[k];
BiTangent += D[k] * BUCP[k];
}
int level = int(inpt[0].v.ptexInfo.z);
Tangent *= 3 * level;
BiTangent *= 3 * level;
vec3 normal = normalize(cross(Tangent, BiTangent));
OSD_COMPUTE_PTEX_COMPATIBLE_TANGENT(OSD_TRANSITION_ROTATE);
#endif
outpt.v.position = vec4(WorldPos, 1.0f);
outpt.v.normal = normal;
OSD_USER_VARYING_PER_EVAL_POINT(UV, 5, 6, 9, 10);
outpt.v.patchCoord = inpt[0].v.patchCoord;
#if OSD_TRANSITION_ROTATE == 1
outpt.v.patchCoord.xy = vec2(UV.y, 1.0-UV.x);
#elif OSD_TRANSITION_ROTATE == 2
outpt.v.patchCoord.xy = vec2(1.0-UV.x, 1.0-UV.y);
#elif OSD_TRANSITION_ROTATE == 3
outpt.v.patchCoord.xy = vec2(1.0-UV.y, UV.x);
#else // OSD_TRANNSITION_ROTATE == 0, or non-transition patch
outpt.v.patchCoord.xy = vec2(UV.x, UV.y);
#endif
OSD_COMPUTE_PTEX_COORD_TESSEVAL_SHADER;
OSD_DISPLACEMENT_CALLBACK;
gl_Position = (OsdProjectionMatrix() * vec4(WorldPos, 1.0f));
}
#endif