From a93aba600b1c5d019b680b9f4ff3fa85d5d43a60 Mon Sep 17 00:00:00 2001 From: allusive-dev Date: Tue, 19 Sep 2023 17:47:33 +1000 Subject: Fixed broken files/code and other errors --- src/kernel.h | 39 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 39 insertions(+) create mode 100644 src/kernel.h (limited to 'src/kernel.h') diff --git a/src/kernel.h b/src/kernel.h new file mode 100644 index 0000000..251d127 --- /dev/null +++ b/src/kernel.h @@ -0,0 +1,39 @@ +// SPDX-License-Identifier: MPL-2.0 +// Copyright (c) Yuxuan Shui + +#pragma once +#include +#include "compiler.h" + +/// Code for generating convolution kernels + +typedef struct conv { + int w, h; + double *rsum; + double data[]; +} conv; + +/// Calculate the sum of a rectangle part of the convolution kernel +/// the rectangle is defined by top left (x, y), and a size (width x height) +double attr_pure sum_kernel(const conv *map, int x, int y, int width, int height); +double attr_pure sum_kernel_normalized(const conv *map, int x, int y, int width, int height); + +/// Create a kernel with gaussian distribution with standard deviation `r`, and size +/// `size`. +conv *gaussian_kernel(double r, int size); + +/// Create a gaussian kernel with auto detected standard deviation. The choosen standard +/// deviation tries to make sure the outer most pixels of the shadow are completely +/// transparent. +/// +/// @param[in] shadow_radius the radius of the shadow +conv *gaussian_kernel_autodetect_deviation(int shadow_radius); + +/// preprocess kernels to make shadow generation faster +/// shadow_sum[x*d+y] is the sum of the kernel from (0, 0) to (x, y), inclusive +void sum_kernel_preprocess(conv *map); + +static inline void free_conv(conv *k) { + free(k->rsum); + free(k); +} -- cgit v1.2.3