76 lines
1.7 KiB
C
76 lines
1.7 KiB
C
/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
|
|
*
|
|
* SPDX-License-Identifier: Apache-2.0 */
|
|
|
|
#pragma once
|
|
|
|
CCL_NAMESPACE_BEGIN
|
|
|
|
/* NOTE: svm_ramp.h, svm_ramp_util.h and node_ramp_util.h must stay consistent */
|
|
|
|
ccl_device_inline float3
|
|
rgb_ramp_lookup(const float3 *ramp, float f, bool interpolate, bool extrapolate, int table_size)
|
|
{
|
|
if ((f < 0.0f || f > 1.0f) && extrapolate) {
|
|
float3 t0, dy;
|
|
if (f < 0.0f) {
|
|
t0 = ramp[0];
|
|
dy = t0 - ramp[1], f = -f;
|
|
}
|
|
else {
|
|
t0 = ramp[table_size - 1];
|
|
dy = t0 - ramp[table_size - 2];
|
|
f = f - 1.0f;
|
|
}
|
|
return t0 + dy * f * (table_size - 1);
|
|
}
|
|
|
|
f = clamp(f, 0.0f, 1.0f) * (table_size - 1);
|
|
|
|
/* clamp int as well in case of NaN */
|
|
int i = clamp(float_to_int(f), 0, table_size - 1);
|
|
float t = f - (float)i;
|
|
|
|
float3 result = ramp[i];
|
|
|
|
if (interpolate && t > 0.0f) {
|
|
result = (1.0f - t) * result + t * ramp[i + 1];
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
ccl_device float float_ramp_lookup(
|
|
const float *ramp, float f, bool interpolate, bool extrapolate, int table_size)
|
|
{
|
|
if ((f < 0.0f || f > 1.0f) && extrapolate) {
|
|
float t0, dy;
|
|
if (f < 0.0f) {
|
|
t0 = ramp[0];
|
|
dy = t0 - ramp[1], f = -f;
|
|
}
|
|
else {
|
|
t0 = ramp[table_size - 1];
|
|
dy = t0 - ramp[table_size - 2];
|
|
f = f - 1.0f;
|
|
}
|
|
return t0 + dy * f * (table_size - 1);
|
|
}
|
|
|
|
f = clamp(f, 0.0f, 1.0f) * (table_size - 1);
|
|
|
|
/* clamp int as well in case of NaN */
|
|
int i = clamp(float_to_int(f), 0, table_size - 1);
|
|
float t = f - (float)i;
|
|
|
|
float result = ramp[i];
|
|
|
|
if (interpolate && t > 0.0f) {
|
|
result = (1.0f - t) * result + t * ramp[i + 1];
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
CCL_NAMESPACE_END
|