Cycles: Add Blackman-Harris filter, fix Gaussian filter

This commit adds the Blackman-Harris windows function as a pixel filter to Cycles. On some cases, such as wireframes or high-frequency textures,
Blackman-Harris can give subtle but noticable improvements over the Gaussian window.
Also, the gaussian window was truncated too early, which degraded quality a bit, therefore the evaluation region is now three times as wide.
To avoid artifacts caused by the wider curve, the filter table size is increased to 1024.

Reviewers: #cycles

Differential Revision: https://developer.blender.org/D1453
This commit is contained in:
Lukas Stockner 2015-08-06 21:04:43 +02:00
parent 24a387d6ff
commit 8dea06565f
Notes: blender-bot 2023-09-08 04:55:43 +02:00
Referenced by issue #47000, Texture paint problem with soft bush gradients
Referenced by issue #46835, Daily build glossy material crashes blender directly.
Referenced by issue #46838, High Quality DOF does not work (Intel)
Referenced by issue #46818, Cycles crashes when glossy, glass, and refraction shaders are used
4 changed files with 16 additions and 3 deletions

View File

@ -54,6 +54,7 @@ enum_bvh_types = (
enum_filter_types = (
('BOX', "Box", "Box filter"),
('GAUSSIAN', "Gaussian", "Gaussian filter"),
('BLACKMAN_HARRIS', "Blackman-Harris", "Blackman-Harris filter"),
)
enum_aperture_types = (

View File

@ -37,7 +37,7 @@ CCL_NAMESPACE_BEGIN
#define OBJECT_SIZE 11
#define OBJECT_VECTOR_SIZE 6
#define LIGHT_SIZE 5
#define FILTER_TABLE_SIZE 256
#define FILTER_TABLE_SIZE 1024
#define RAMP_TABLE_SIZE 256
#define SHUTTER_TABLE_SIZE 256
#define PARTICLE_SIZE 5

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@ -209,10 +209,16 @@ static float filter_func_box(float /*v*/, float /*width*/)
static float filter_func_gaussian(float v, float width)
{
v *= 2.0f/width;
v *= 6.0f/width;
return expf(-2.0f*v*v);
}
static float filter_func_blackman_harris(float v, float width)
{
v = M_2PI_F * (v / width + 0.5f);
return 0.35875f - 0.48829f*cosf(v) + 0.14128f*cosf(2.0f*v) - 0.01168f*cosf(3.0f*v);
}
static vector<float> filter_table(FilterType type, float width)
{
vector<float> filter_table(FILTER_TABLE_SIZE);
@ -224,6 +230,11 @@ static vector<float> filter_table(FilterType type, float width)
break;
case FILTER_GAUSSIAN:
filter_func = filter_func_gaussian;
width *= 3.0f;
break;
case FILTER_BLACKMAN_HARRIS:
filter_func = filter_func_blackman_harris;
width *= 2.0f;
break;
default:
assert(0);

View File

@ -30,7 +30,8 @@ class Scene;
typedef enum FilterType {
FILTER_BOX,
FILTER_GAUSSIAN
FILTER_GAUSSIAN,
FILTER_BLACKMAN_HARRIS
} FilterType;
class Pass {