blender/intern/cycles/kernel/geom/geom_primitive.h
Brecht Van Lommel 27043b8e40 Cycles code internals: add support for mesh voxel grid attributes.
These are internally stored as a 3D image textures, but accessible like e.g.
UV coordinates though the attribute node and getattribute().

This is convenient for rendering e.g. smoke objects where data like density is
really a property of the mesh, and it avoids having to specify the smoke object
in a texture node, instead the material will work with any smoke domain.
2014-03-29 13:03:48 +01:00

213 lines
6.5 KiB
C

/*
* Copyright 2011-2013 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
*/
/* Primitive Utilities
*
* Generic functions to look up mesh, curve and volume primitive attributes for
* shading and render passes. */
CCL_NAMESPACE_BEGIN
/* Generic primitive attribute reading functions */
ccl_device float primitive_attribute_float(KernelGlobals *kg, const ShaderData *sd, AttributeElement elem, int offset, float *dx, float *dy)
{
if(sd->type & PRIMITIVE_ALL_TRIANGLE) {
return triangle_attribute_float(kg, sd, elem, offset, dx, dy);
}
#ifdef __HAIR__
else if(sd->type & PRIMITIVE_ALL_CURVE) {
return curve_attribute_float(kg, sd, elem, offset, dx, dy);
}
#endif
#ifdef __VOLUME__
else if(sd->object != OBJECT_NONE && elem == ATTR_ELEMENT_VOXEL) {
return volume_attribute_float(kg, sd, elem, offset, dx, dy);
}
#endif
else {
if(dx) *dx = 0.0f;
if(dy) *dy = 0.0f;
return 0.0f;
}
}
ccl_device float3 primitive_attribute_float3(KernelGlobals *kg, const ShaderData *sd, AttributeElement elem, int offset, float3 *dx, float3 *dy)
{
if(sd->type & PRIMITIVE_ALL_TRIANGLE) {
return triangle_attribute_float3(kg, sd, elem, offset, dx, dy);
}
#ifdef __HAIR__
else if(sd->type & PRIMITIVE_ALL_CURVE) {
return curve_attribute_float3(kg, sd, elem, offset, dx, dy);
}
#endif
#ifdef __VOLUME__
else if(sd->object != OBJECT_NONE && elem == ATTR_ELEMENT_VOXEL) {
return volume_attribute_float3(kg, sd, elem, offset, dx, dy);
}
#endif
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);
}
}
/* Default UV coordinate */
ccl_device float3 primitive_uv(KernelGlobals *kg, ShaderData *sd)
{
AttributeElement elem_uv;
int offset_uv = find_attribute(kg, sd, ATTR_STD_UV, &elem_uv);
if(offset_uv == ATTR_STD_NOT_FOUND)
return make_float3(0.0f, 0.0f, 0.0f);
float3 uv = primitive_attribute_float3(kg, sd, elem_uv, offset_uv, NULL, NULL);
uv.z = 1.0f;
return uv;
}
/* Ptex coordinates */
ccl_device bool primitive_ptex(KernelGlobals *kg, ShaderData *sd, float2 *uv, int *face_id)
{
/* storing ptex data as attributes is not memory efficient but simple for tests */
AttributeElement elem_face_id, elem_uv;
int offset_face_id = find_attribute(kg, sd, ATTR_STD_PTEX_FACE_ID, &elem_face_id);
int offset_uv = find_attribute(kg, sd, ATTR_STD_PTEX_UV, &elem_uv);
if(offset_face_id == ATTR_STD_NOT_FOUND || offset_uv == ATTR_STD_NOT_FOUND)
return false;
float3 uv3 = primitive_attribute_float3(kg, sd, elem_uv, offset_uv, NULL, NULL);
float face_id_f = primitive_attribute_float(kg, sd, elem_face_id, offset_face_id, NULL, NULL);
*uv = make_float2(uv3.x, uv3.y);
*face_id = (int)face_id_f;
return true;
}
/* Surface tangent */
ccl_device float3 primitive_tangent(KernelGlobals *kg, ShaderData *sd)
{
#ifdef __HAIR__
if(sd->type & PRIMITIVE_ALL_CURVE)
#ifdef __DPDU__
return normalize(sd->dPdu);
#else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
#endif
/* try to create spherical tangent from generated coordinates */
AttributeElement attr_elem;
int attr_offset = find_attribute(kg, sd, ATTR_STD_GENERATED, &attr_elem);
if(attr_offset != ATTR_STD_NOT_FOUND) {
float3 data = primitive_attribute_float3(kg, sd, attr_elem, attr_offset, NULL, NULL);
data = make_float3(-(data.y - 0.5f), (data.x - 0.5f), 0.0f);
object_normal_transform(kg, sd, &data);
return cross(sd->N, normalize(cross(data, sd->N)));
}
else {
/* otherwise use surface derivatives */
#ifdef __DPDU__
return normalize(sd->dPdu);
#else
return make_float3(0.0f, 0.0f, 0.0f);
#endif
}
}
/* Motion vector for motion pass */
ccl_device float4 primitive_motion_vector(KernelGlobals *kg, ShaderData *sd)
{
float3 motion_pre = sd->P, motion_post = sd->P;
/* deformation motion */
AttributeElement elem;
int offset = find_attribute(kg, sd, ATTR_STD_MOTION_VERTEX_POSITION, &elem);
if(offset != ATTR_STD_NOT_FOUND) {
/* get motion info */
int numverts, numkeys;
object_motion_info(kg, sd->object, NULL, &numverts, &numkeys);
/* lookup attributes */
int offset_next = (sd->type & PRIMITIVE_ALL_TRIANGLE)? offset + numverts: offset + numkeys;
motion_pre = primitive_attribute_float3(kg, sd, elem, offset, NULL, NULL);
motion_post = primitive_attribute_float3(kg, sd, elem, offset_next, NULL, NULL);
}
/* object motion. note that depending on the mesh having motion vectors, this
* transformation was set match the world/object space of motion_pre/post */
Transform tfm;
tfm = object_fetch_vector_transform(kg, sd->object, OBJECT_VECTOR_MOTION_PRE);
motion_pre = transform_point(&tfm, motion_pre);
tfm = object_fetch_vector_transform(kg, sd->object, OBJECT_VECTOR_MOTION_POST);
motion_post = transform_point(&tfm, motion_post);
float3 P;
/* camera motion, for perspective/orthographic motion.pre/post will be a
* world-to-raster matrix, for panorama it's world-to-camera */
if (kernel_data.cam.type != CAMERA_PANORAMA) {
tfm = kernel_data.cam.worldtoraster;
P = transform_perspective(&tfm, sd->P);
tfm = kernel_data.cam.motion.pre;
motion_pre = transform_perspective(&tfm, motion_pre);
tfm = kernel_data.cam.motion.post;
motion_post = transform_perspective(&tfm, motion_post);
}
else {
tfm = kernel_data.cam.worldtocamera;
P = normalize(transform_point(&tfm, sd->P));
P = float2_to_float3(direction_to_panorama(kg, P));
P.x *= kernel_data.cam.width;
P.y *= kernel_data.cam.height;
tfm = kernel_data.cam.motion.pre;
motion_pre = normalize(transform_point(&tfm, motion_pre));
motion_pre = float2_to_float3(direction_to_panorama(kg, motion_pre));
motion_pre.x *= kernel_data.cam.width;
motion_pre.y *= kernel_data.cam.height;
tfm = kernel_data.cam.motion.post;
motion_post = normalize(transform_point(&tfm, motion_post));
motion_post = float2_to_float3(direction_to_panorama(kg, motion_post));
motion_post.x *= kernel_data.cam.width;
motion_post.y *= kernel_data.cam.height;
}
motion_pre = motion_pre - P;
motion_post = P - motion_post;
return make_float4(motion_pre.x, motion_pre.y, motion_post.x, motion_post.y);
}
CCL_NAMESPACE_END