71 lines
2.1 KiB
C
71 lines
2.1 KiB
C
/* SPDX-FileCopyrightText: 2021-2022 Blender Foundation
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0 */
|
|
|
|
#pragma once
|
|
|
|
#include "kernel/globals.h"
|
|
|
|
#include "kernel/bvh/util.h"
|
|
|
|
CCL_NAMESPACE_BEGIN
|
|
|
|
/* Motion Point Primitive
|
|
*
|
|
* These are stored as regular points, plus extra positions and radii at times
|
|
* other than the frame center. Computing the point at a given ray time is
|
|
* a matter of interpolation of the two steps between which the ray time lies.
|
|
*
|
|
* The extra points are stored as ATTR_STD_MOTION_VERTEX_POSITION.
|
|
*/
|
|
|
|
#ifdef __POINTCLOUD__
|
|
|
|
ccl_device_inline float4 motion_point_for_step(
|
|
KernelGlobals kg, int offset, const int numverts, const int numsteps, int step, const int prim)
|
|
{
|
|
if (step == numsteps) {
|
|
/* center step: regular key location */
|
|
return kernel_data_fetch(points, prim);
|
|
}
|
|
/* center step is not stored in this array */
|
|
if (step > numsteps) {
|
|
step--;
|
|
}
|
|
|
|
offset += step * numverts;
|
|
|
|
return kernel_data_fetch(attributes_float4, offset + prim);
|
|
}
|
|
|
|
/* return 2 point key locations */
|
|
ccl_device_inline float4 motion_point(KernelGlobals kg,
|
|
const int object,
|
|
const int prim,
|
|
const float time)
|
|
{
|
|
/* get motion info */
|
|
const int numsteps = kernel_data_fetch(objects, object).numsteps;
|
|
const int numverts = kernel_data_fetch(objects, object).numverts;
|
|
|
|
/* figure out which steps we need to fetch and their interpolation factor */
|
|
const int maxstep = numsteps * 2;
|
|
const int step = min((int)(time * maxstep), maxstep - 1);
|
|
const float t = time * maxstep - step;
|
|
|
|
/* find attribute */
|
|
const int offset = intersection_find_attribute(kg, object, ATTR_STD_MOTION_VERTEX_POSITION);
|
|
kernel_assert(offset != ATTR_STD_NOT_FOUND);
|
|
|
|
/* fetch key coordinates */
|
|
const float4 point = motion_point_for_step(kg, offset, numverts, numsteps, step, prim);
|
|
const float4 next_point = motion_point_for_step(kg, offset, numverts, numsteps, step + 1, prim);
|
|
|
|
/* interpolate between steps */
|
|
return (1.0f - t) * point + t * next_point;
|
|
}
|
|
|
|
#endif
|
|
|
|
CCL_NAMESPACE_END
|