diff options
Diffstat (limited to 'intern/cycles/kernel/util/util_lookup_table.h')
-rw-r--r-- | intern/cycles/kernel/util/util_lookup_table.h | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/intern/cycles/kernel/util/util_lookup_table.h b/intern/cycles/kernel/util/util_lookup_table.h new file mode 100644 index 00000000000..2c26e668d7b --- /dev/null +++ b/intern/cycles/kernel/util/util_lookup_table.h @@ -0,0 +1,56 @@ +/* + * 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. + */ + +#pragma once + +CCL_NAMESPACE_BEGIN + +/* Interpolated lookup table access */ + +ccl_device float lookup_table_read(KernelGlobals kg, float x, int offset, int size) +{ + x = saturate(x) * (size - 1); + + int index = min(float_to_int(x), size - 1); + int nindex = min(index + 1, size - 1); + float t = x - index; + + float data0 = kernel_tex_fetch(__lookup_table, index + offset); + if (t == 0.0f) + return data0; + + float data1 = kernel_tex_fetch(__lookup_table, nindex + offset); + return (1.0f - t) * data0 + t * data1; +} + +ccl_device float lookup_table_read_2D( + KernelGlobals kg, float x, float y, int offset, int xsize, int ysize) +{ + y = saturate(y) * (ysize - 1); + + int index = min(float_to_int(y), ysize - 1); + int nindex = min(index + 1, ysize - 1); + float t = y - index; + + float data0 = lookup_table_read(kg, x, offset + xsize * index, xsize); + if (t == 0.0f) + return data0; + + float data1 = lookup_table_read(kg, x, offset + xsize * nindex, xsize); + return (1.0f - t) * data0 + t * data1; +} + +CCL_NAMESPACE_END |