blender/intern/cycles/kernel/kernel_camera.h
Brecht Van Lommel 99f5993088 Cycles code refactor: improve vertex motion attribute storage and export.
This now supports multiple steps and subframe sampling of motion.

There is one difference for object and camera transform motion blur. It still
only supports two steps there, but the transforms are now sampled at subframe
times instead of the previous and next frame and then interpolated/extrapolated.
This will give different render results in some cases but it's more accurate.

Part of the code is from the summer of code project by Gavin Howard, but it has
been significantly rewritten and extended.
2014-03-29 13:03:46 +01:00

292 lines
8.7 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
*/
CCL_NAMESPACE_BEGIN
/* Perspective Camera */
ccl_device float2 camera_sample_aperture(KernelGlobals *kg, float u, float v)
{
float blades = kernel_data.cam.blades;
if(blades == 0.0f) {
/* sample disk */
return concentric_sample_disk(u, v);
}
else {
/* sample polygon */
float rotation = kernel_data.cam.bladesrotation;
return regular_polygon_sample(blades, rotation, u, v);
}
}
ccl_device void camera_sample_perspective(KernelGlobals *kg, float raster_x, float raster_y, float lens_u, float lens_v, Ray *ray)
{
/* create ray form raster position */
Transform rastertocamera = kernel_data.cam.rastertocamera;
float3 Pcamera = transform_perspective(&rastertocamera, make_float3(raster_x, raster_y, 0.0f));
ray->P = make_float3(0.0f, 0.0f, 0.0f);
ray->D = Pcamera;
/* modify ray for depth of field */
float aperturesize = kernel_data.cam.aperturesize;
if(aperturesize > 0.0f) {
/* sample point on aperture */
float2 lensuv = camera_sample_aperture(kg, lens_u, lens_v)*aperturesize;
/* compute point on plane of focus */
float ft = kernel_data.cam.focaldistance/ray->D.z;
float3 Pfocus = ray->D*ft;
/* update ray for effect of lens */
ray->P = make_float3(lensuv.x, lensuv.y, 0.0f);
ray->D = normalize(Pfocus - ray->P);
}
/* transform ray from camera to world */
Transform cameratoworld = kernel_data.cam.cameratoworld;
#ifdef __CAMERA_MOTION__
if(kernel_data.cam.have_motion)
transform_motion_interpolate(&cameratoworld, (const DecompMotionTransform*)&kernel_data.cam.motion, ray->time);
#endif
ray->P = transform_point(&cameratoworld, ray->P);
ray->D = transform_direction(&cameratoworld, ray->D);
ray->D = normalize(ray->D);
#ifdef __RAY_DIFFERENTIALS__
/* ray differential */
float3 Ddiff = transform_direction(&cameratoworld, Pcamera);
ray->dP = differential3_zero();
ray->dD.dx = normalize(Ddiff + float4_to_float3(kernel_data.cam.dx)) - normalize(Ddiff);
ray->dD.dy = normalize(Ddiff + float4_to_float3(kernel_data.cam.dy)) - normalize(Ddiff);
#endif
#ifdef __CAMERA_CLIPPING__
/* clipping */
ray->P += kernel_data.cam.nearclip*ray->D;
ray->t = kernel_data.cam.cliplength;
#else
ray->t = FLT_MAX;
#endif
}
/* Orthographic Camera */
ccl_device void camera_sample_orthographic(KernelGlobals *kg, float raster_x, float raster_y, float lens_u, float lens_v, Ray *ray)
{
/* create ray form raster position */
Transform rastertocamera = kernel_data.cam.rastertocamera;
float3 Pcamera = transform_perspective(&rastertocamera, make_float3(raster_x, raster_y, 0.0f));
ray->D = make_float3(0.0f, 0.0f, 1.0f);
/* modify ray for depth of field */
float aperturesize = kernel_data.cam.aperturesize;
if(aperturesize > 0.0f) {
/* sample point on aperture */
float2 lensuv = camera_sample_aperture(kg, lens_u, lens_v)*aperturesize;
/* compute point on plane of focus */
float3 Pfocus = ray->D * kernel_data.cam.focaldistance;
/* update ray for effect of lens */
float3 lensuvw = make_float3(lensuv.x, lensuv.y, 0.0f);
ray->P = Pcamera + lensuvw;
ray->D = normalize(Pfocus - lensuvw);
}
else {
ray->P = Pcamera;
}
/* transform ray from camera to world */
Transform cameratoworld = kernel_data.cam.cameratoworld;
#ifdef __CAMERA_MOTION__
if(kernel_data.cam.have_motion)
transform_motion_interpolate(&cameratoworld, (const DecompMotionTransform*)&kernel_data.cam.motion, ray->time);
#endif
ray->P = transform_point(&cameratoworld, ray->P);
ray->D = transform_direction(&cameratoworld, ray->D);
ray->D = normalize(ray->D);
#ifdef __RAY_DIFFERENTIALS__
/* ray differential */
ray->dP.dx = float4_to_float3(kernel_data.cam.dx);
ray->dP.dy = float4_to_float3(kernel_data.cam.dy);
ray->dD = differential3_zero();
#endif
#ifdef __CAMERA_CLIPPING__
/* clipping */
ray->t = kernel_data.cam.cliplength;
#else
ray->t = FLT_MAX;
#endif
}
/* Panorama Camera */
ccl_device void camera_sample_panorama(KernelGlobals *kg, float raster_x, float raster_y, float lens_u, float lens_v, Ray *ray)
{
Transform rastertocamera = kernel_data.cam.rastertocamera;
float3 Pcamera = transform_perspective(&rastertocamera, make_float3(raster_x, raster_y, 0.0f));
/* create ray form raster position */
ray->P = make_float3(0.0f, 0.0f, 0.0f);
#ifdef __CAMERA_CLIPPING__
/* clipping */
ray->t = kernel_data.cam.cliplength;
#else
ray->t = FLT_MAX;
#endif
ray->D = panorama_to_direction(kg, Pcamera.x, Pcamera.y);
/* indicates ray should not receive any light, outside of the lens */
if(is_zero(ray->D)) {
ray->t = 0.0f;
return;
}
/* modify ray for depth of field */
float aperturesize = kernel_data.cam.aperturesize;
if(aperturesize > 0.0f) {
/* sample point on aperture */
float2 lensuv = camera_sample_aperture(kg, lens_u, lens_v)*aperturesize;
/* compute point on plane of focus */
float3 D = normalize(ray->D);
float3 Pfocus = D * kernel_data.cam.focaldistance;
/* calculate orthonormal coordinates perpendicular to D */
float3 U, V;
make_orthonormals(D, &U, &V);
/* update ray for effect of lens */
ray->P = U * lensuv.x + V * lensuv.y;
ray->D = normalize(Pfocus - ray->P);
}
/* transform ray from camera to world */
Transform cameratoworld = kernel_data.cam.cameratoworld;
#ifdef __CAMERA_MOTION__
if(kernel_data.cam.have_motion)
transform_motion_interpolate(&cameratoworld, (const DecompMotionTransform*)&kernel_data.cam.motion, ray->time);
#endif
ray->P = transform_point(&cameratoworld, ray->P);
ray->D = transform_direction(&cameratoworld, ray->D);
ray->D = normalize(ray->D);
#ifdef __RAY_DIFFERENTIALS__
/* ray differential */
ray->dP = differential3_zero();
Pcamera = transform_perspective(&rastertocamera, make_float3(raster_x + 1.0f, raster_y, 0.0f));
ray->dD.dx = normalize(transform_direction(&cameratoworld, panorama_to_direction(kg, Pcamera.x, Pcamera.y))) - ray->D;
Pcamera = transform_perspective(&rastertocamera, make_float3(raster_x, raster_y + 1.0f, 0.0f));
ray->dD.dy = normalize(transform_direction(&cameratoworld, panorama_to_direction(kg, Pcamera.x, Pcamera.y))) - ray->D;
#endif
}
/* Common */
ccl_device void camera_sample(KernelGlobals *kg, int x, int y, float filter_u, float filter_v,
float lens_u, float lens_v, float time, Ray *ray)
{
/* pixel filter */
int filter_table_offset = kernel_data.film.filter_table_offset;
float raster_x = x + lookup_table_read(kg, filter_u, filter_table_offset, FILTER_TABLE_SIZE);
float raster_y = y + lookup_table_read(kg, filter_v, filter_table_offset, FILTER_TABLE_SIZE);
#ifdef __CAMERA_MOTION__
/* motion blur */
if(kernel_data.cam.shuttertime == -1.0f)
ray->time = TIME_INVALID;
else
ray->time = time;
#endif
/* sample */
if(kernel_data.cam.type == CAMERA_PERSPECTIVE)
camera_sample_perspective(kg, raster_x, raster_y, lens_u, lens_v, ray);
else if(kernel_data.cam.type == CAMERA_ORTHOGRAPHIC)
camera_sample_orthographic(kg, raster_x, raster_y, lens_u, lens_v, ray);
else
camera_sample_panorama(kg, raster_x, raster_y, lens_u, lens_v, ray);
}
/* Utilities */
ccl_device_inline float3 camera_position(KernelGlobals *kg)
{
Transform cameratoworld = kernel_data.cam.cameratoworld;
return make_float3(cameratoworld.x.w, cameratoworld.y.w, cameratoworld.z.w);
}
ccl_device_inline float camera_distance(KernelGlobals *kg, float3 P)
{
Transform cameratoworld = kernel_data.cam.cameratoworld;
float3 camP = make_float3(cameratoworld.x.w, cameratoworld.y.w, cameratoworld.z.w);
if(kernel_data.cam.type == CAMERA_ORTHOGRAPHIC) {
float3 camD = make_float3(cameratoworld.x.z, cameratoworld.y.z, cameratoworld.z.z);
return fabsf(dot((P - camP), camD));
}
else
return len(P - camP);
}
ccl_device_inline float3 camera_world_to_ndc(KernelGlobals *kg, ShaderData *sd, float3 P)
{
if(kernel_data.cam.type != CAMERA_PANORAMA) {
/* perspective / ortho */
if(sd->object == ~0 && kernel_data.cam.type == CAMERA_PERSPECTIVE)
P += camera_position(kg);
Transform tfm = kernel_data.cam.worldtondc;
return transform_perspective(&tfm, P);
}
else {
/* panorama */
Transform tfm = kernel_data.cam.worldtocamera;
if(sd->object != ~0)
P = normalize(transform_point(&tfm, P));
else
P = normalize(transform_direction(&tfm, P));
float2 uv = direction_to_panorama(kg, P);
return make_float3(uv.x, uv.y, 0.0f);
}
}
CCL_NAMESPACE_END