blender/intern/cycles/kernel/geom/geom_triangle.h
George Kyriazis 7f4479da42 Cycles: OpenCL kernel split
This commit contains all the work related on the AMD megakernel split work
which was mainly done by Varun Sundar, George Kyriazis and Lenny Wang, plus
some help from Sergey Sharybin, Martijn Berger, Thomas Dinges and likely
someone else which we're forgetting to mention.

Currently only AMD cards are enabled for the new split kernel, but it is
possible to force split opencl kernel to be used by setting the following
environment variable: CYCLES_OPENCL_SPLIT_KERNEL_TEST=1.

Not all the features are supported yet, and that being said no motion blur,
camera blur, SSS and volumetrics for now. Also transparent shadows are
disabled on AMD device because of some compiler bug.

This kernel is also only implements regular path tracing and supporting
branched one will take a bit. Branched path tracing is exposed to the
interface still, which is a bit misleading and will be hidden there soon.

More feature will be enabled once they're ported to the split kernel and
tested.

Neither regular CPU nor CUDA has any difference, they're generating the
same exact code, which means no regressions/improvements there.

Based on the research paper:

  https://research.nvidia.com/sites/default/files/publications/laine2013hpg_paper.pdf

Here's the documentation:

  https://docs.google.com/document/d/1LuXW-CV-sVJkQaEGZlMJ86jZ8FmoPfecaMdR-oiWbUY/edit

Design discussion of the patch:

  https://developer.blender.org/T44197

Differential Revision: https://developer.blender.org/D1200
2015-05-09 19:52:40 +05:00

209 lines
8.3 KiB
C

/*
* Adapted from code Copyright 2009-2010 NVIDIA Corporation
* Modifications Copyright 2011, Blender Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* 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.
*/
/* Triangle Primitive
*
* Basic triangle with 3 vertices is used to represent mesh surfaces. For BVH
* ray intersection we use a precomputed triangle storage to accelerate
* intersection at the cost of more memory usage */
CCL_NAMESPACE_BEGIN
/* normal on triangle */
ccl_device_inline float3 triangle_normal(KernelGlobals *kg, ShaderData *sd)
{
/* load triangle vertices */
float4 tri_vindex = kernel_tex_fetch(__tri_vindex, ccl_fetch(sd, prim));
float3 v0 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.x)));
float3 v1 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.y)));
float3 v2 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.z)));
/* return normal */
if(ccl_fetch(sd, flag) & SD_NEGATIVE_SCALE_APPLIED)
return normalize(cross(v2 - v0, v1 - v0));
else
return normalize(cross(v1 - v0, v2 - v0));
}
/* point and normal on triangle */
ccl_device_inline void triangle_point_normal(KernelGlobals *kg, int object, int prim, float u, float v, float3 *P, float3 *Ng, int *shader)
{
/* load triangle vertices */
float4 tri_vindex = kernel_tex_fetch(__tri_vindex, prim);
float3 v0 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.x)));
float3 v1 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.y)));
float3 v2 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.z)));
/* compute point */
float t = 1.0f - u - v;
*P = (u*v0 + v*v1 + t*v2);
/* get object flags, instance-aware */
int object_flag = kernel_tex_fetch(__object_flag, object >= 0 ? object : ~object);
/* compute normal */
if(object_flag & SD_NEGATIVE_SCALE_APPLIED)
*Ng = normalize(cross(v2 - v0, v1 - v0));
else
*Ng = normalize(cross(v1 - v0, v2 - v0));
/* shader`*/
*shader = kernel_tex_fetch(__tri_shader, prim);
}
/* Triangle vertex locations */
ccl_device_inline void triangle_vertices(KernelGlobals *kg, int prim, float3 P[3])
{
float4 tri_vindex = kernel_tex_fetch(__tri_vindex, prim);
P[0] = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.x)));
P[1] = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.y)));
P[2] = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.z)));
}
/* Interpolate smooth vertex normal from vertices */
ccl_device_inline float3 triangle_smooth_normal(KernelGlobals *kg, int prim, float u, float v)
{
/* load triangle vertices */
float4 tri_vindex = kernel_tex_fetch(__tri_vindex, prim);
float3 n0 = float4_to_float3(kernel_tex_fetch(__tri_vnormal, __float_as_int(tri_vindex.x)));
float3 n1 = float4_to_float3(kernel_tex_fetch(__tri_vnormal, __float_as_int(tri_vindex.y)));
float3 n2 = float4_to_float3(kernel_tex_fetch(__tri_vnormal, __float_as_int(tri_vindex.z)));
return normalize((1.0f - u - v)*n2 + u*n0 + v*n1);
}
/* Ray differentials on triangle */
ccl_device_inline void triangle_dPdudv(KernelGlobals *kg, int prim, ccl_addr_space float3 *dPdu, ccl_addr_space float3 *dPdv)
{
/* fetch triangle vertex coordinates */
float4 tri_vindex = kernel_tex_fetch(__tri_vindex, prim);
float3 p0 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.x)));
float3 p1 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.y)));
float3 p2 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.z)));
/* compute derivatives of P w.r.t. uv */
*dPdu = (p0 - p2);
*dPdv = (p1 - p2);
}
/* Reading attributes on various triangle elements */
ccl_device float triangle_attribute_float(KernelGlobals *kg, const ShaderData *sd, AttributeElement elem, int offset, float *dx, float *dy)
{
if(elem == ATTR_ELEMENT_FACE) {
if(dx) *dx = 0.0f;
if(dy) *dy = 0.0f;
return kernel_tex_fetch(__attributes_float, offset + ccl_fetch(sd, prim));
}
else if(elem == ATTR_ELEMENT_VERTEX || elem == ATTR_ELEMENT_VERTEX_MOTION) {
float4 tri_vindex = kernel_tex_fetch(__tri_vindex, ccl_fetch(sd, prim));
float f0 = kernel_tex_fetch(__attributes_float, offset + __float_as_int(tri_vindex.x));
float f1 = kernel_tex_fetch(__attributes_float, offset + __float_as_int(tri_vindex.y));
float f2 = kernel_tex_fetch(__attributes_float, offset + __float_as_int(tri_vindex.z));
#ifdef __RAY_DIFFERENTIALS__
if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
#endif
return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
}
else if(elem == ATTR_ELEMENT_CORNER) {
int tri = offset + ccl_fetch(sd, prim)*3;
float f0 = kernel_tex_fetch(__attributes_float, tri + 0);
float f1 = kernel_tex_fetch(__attributes_float, tri + 1);
float f2 = kernel_tex_fetch(__attributes_float, tri + 2);
#ifdef __RAY_DIFFERENTIALS__
if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
#endif
return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
}
else {
if(dx) *dx = 0.0f;
if(dy) *dy = 0.0f;
return 0.0f;
}
}
ccl_device float3 triangle_attribute_float3(KernelGlobals *kg, const ShaderData *sd, AttributeElement elem, int offset, float3 *dx, float3 *dy)
{
if(elem == ATTR_ELEMENT_FACE) {
if(dx) *dx = make_float3(0.0f, 0.0f, 0.0f);
if(dy) *dy = make_float3(0.0f, 0.0f, 0.0f);
return float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + ccl_fetch(sd, prim)));
}
else if(elem == ATTR_ELEMENT_VERTEX || elem == ATTR_ELEMENT_VERTEX_MOTION) {
float4 tri_vindex = kernel_tex_fetch(__tri_vindex, ccl_fetch(sd, prim));
float3 f0 = float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + __float_as_int(tri_vindex.x)));
float3 f1 = float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + __float_as_int(tri_vindex.y)));
float3 f2 = float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + __float_as_int(tri_vindex.z)));
#ifdef __RAY_DIFFERENTIALS__
if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
#endif
return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
}
else if(elem == ATTR_ELEMENT_CORNER || elem == ATTR_ELEMENT_CORNER_BYTE) {
int tri = offset + ccl_fetch(sd, prim)*3;
float3 f0, f1, f2;
if(elem == ATTR_ELEMENT_CORNER) {
f0 = float4_to_float3(kernel_tex_fetch(__attributes_float3, tri + 0));
f1 = float4_to_float3(kernel_tex_fetch(__attributes_float3, tri + 1));
f2 = float4_to_float3(kernel_tex_fetch(__attributes_float3, tri + 2));
}
else {
f0 = color_byte_to_float(kernel_tex_fetch(__attributes_uchar4, tri + 0));
f1 = color_byte_to_float(kernel_tex_fetch(__attributes_uchar4, tri + 1));
f2 = color_byte_to_float(kernel_tex_fetch(__attributes_uchar4, tri + 2));
}
#ifdef __RAY_DIFFERENTIALS__
if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
#endif
return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
}
else {
if(dx) *dx = make_float3(0.0f, 0.0f, 0.0f);
if(dy) *dy = make_float3(0.0f, 0.0f, 0.0f);
return make_float3(0.0f, 0.0f, 0.0f);
}
}
CCL_NAMESPACE_END