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Diffstat (limited to 'qemu/pixman/pixman/pixman-filter.c')
-rw-r--r-- | qemu/pixman/pixman/pixman-filter.c | 350 |
1 files changed, 0 insertions, 350 deletions
diff --git a/qemu/pixman/pixman/pixman-filter.c b/qemu/pixman/pixman/pixman-filter.c deleted file mode 100644 index b2bf53fed..000000000 --- a/qemu/pixman/pixman/pixman-filter.c +++ /dev/null @@ -1,350 +0,0 @@ -/* - * Copyright 2012, Red Hat, Inc. - * Copyright 2012, Soren Sandmann - * - * Permission is hereby granted, free of charge, to any person obtaining a - * copy of this software and associated documentation files (the "Software"), - * to deal in the Software without restriction, including without limitation - * the rights to use, copy, modify, merge, publish, distribute, sublicense, - * and/or sell copies of the Software, and to permit persons to whom the - * Software is furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice (including the next - * paragraph) shall be included in all copies or substantial portions of the - * Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING - * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER - * DEALINGS IN THE SOFTWARE. - * - * Author: Soren Sandmann <soren.sandmann@gmail.com> - */ -#include <string.h> -#include <stdlib.h> -#include <stdio.h> -#include <math.h> -#include <assert.h> -#ifdef HAVE_CONFIG_H -#include <config.h> -#endif -#include "pixman-private.h" - -typedef double (* kernel_func_t) (double x); - -typedef struct -{ - pixman_kernel_t kernel; - kernel_func_t func; - double width; -} filter_info_t; - -static double -impulse_kernel (double x) -{ - return (x == 0.0)? 1.0 : 0.0; -} - -static double -box_kernel (double x) -{ - return 1; -} - -static double -linear_kernel (double x) -{ - return 1 - fabs (x); -} - -static double -gaussian_kernel (double x) -{ -#define SQRT2 (1.4142135623730950488016887242096980785696718753769480) -#define SIGMA (SQRT2 / 2.0) - - return exp (- x * x / (2 * SIGMA * SIGMA)) / (SIGMA * sqrt (2.0 * M_PI)); -} - -static double -sinc (double x) -{ - if (x == 0.0) - return 1.0; - else - return sin (M_PI * x) / (M_PI * x); -} - -static double -lanczos (double x, int n) -{ - return sinc (x) * sinc (x * (1.0 / n)); -} - -static double -lanczos2_kernel (double x) -{ - return lanczos (x, 2); -} - -static double -lanczos3_kernel (double x) -{ - return lanczos (x, 3); -} - -static double -nice_kernel (double x) -{ - return lanczos3_kernel (x * 0.75); -} - -static double -general_cubic (double x, double B, double C) -{ - double ax = fabs(x); - - if (ax < 1) - { - return ((12 - 9 * B - 6 * C) * ax * ax * ax + - (-18 + 12 * B + 6 * C) * ax * ax + (6 - 2 * B)) / 6; - } - else if (ax >= 1 && ax < 2) - { - return ((-B - 6 * C) * ax * ax * ax + - (6 * B + 30 * C) * ax * ax + (-12 * B - 48 * C) * - ax + (8 * B + 24 * C)) / 6; - } - else - { - return 0; - } -} - -static double -cubic_kernel (double x) -{ - /* This is the Mitchell-Netravali filter. - * - * (0.0, 0.5) would give us the Catmull-Rom spline, - * but that one seems to be indistinguishable from Lanczos2. - */ - return general_cubic (x, 1/3.0, 1/3.0); -} - -static const filter_info_t filters[] = -{ - { PIXMAN_KERNEL_IMPULSE, impulse_kernel, 0.0 }, - { PIXMAN_KERNEL_BOX, box_kernel, 1.0 }, - { PIXMAN_KERNEL_LINEAR, linear_kernel, 2.0 }, - { PIXMAN_KERNEL_CUBIC, cubic_kernel, 4.0 }, - { PIXMAN_KERNEL_GAUSSIAN, gaussian_kernel, 6 * SIGMA }, - { PIXMAN_KERNEL_LANCZOS2, lanczos2_kernel, 4.0 }, - { PIXMAN_KERNEL_LANCZOS3, lanczos3_kernel, 6.0 }, - { PIXMAN_KERNEL_LANCZOS3_STRETCHED, nice_kernel, 8.0 }, -}; - -/* This function scales @kernel2 by @scale, then - * aligns @x1 in @kernel1 with @x2 in @kernel2 and - * and integrates the product of the kernels across @width. - * - * This function assumes that the intervals are within - * the kernels in question. E.g., the caller must not - * try to integrate a linear kernel ouside of [-1:1] - */ -static double -integral (pixman_kernel_t kernel1, double x1, - pixman_kernel_t kernel2, double scale, double x2, - double width) -{ - /* If the integration interval crosses zero, break it into - * two separate integrals. This ensures that filters such - * as LINEAR that are not differentiable at 0 will still - * integrate properly. - */ - if (x1 < 0 && x1 + width > 0) - { - return - integral (kernel1, x1, kernel2, scale, x2, - x1) + - integral (kernel1, 0, kernel2, scale, x2 - x1, width + x1); - } - else if (x2 < 0 && x2 + width > 0) - { - return - integral (kernel1, x1, kernel2, scale, x2, - x2) + - integral (kernel1, x1 - x2, kernel2, scale, 0, width + x2); - } - else if (kernel1 == PIXMAN_KERNEL_IMPULSE) - { - assert (width == 0.0); - return filters[kernel2].func (x2 * scale); - } - else if (kernel2 == PIXMAN_KERNEL_IMPULSE) - { - assert (width == 0.0); - return filters[kernel1].func (x1); - } - else - { - /* Integration via Simpson's rule */ -#define N_SEGMENTS 128 -#define SAMPLE(a1, a2) \ - (filters[kernel1].func ((a1)) * filters[kernel2].func ((a2) * scale)) - - double s = 0.0; - double h = width / (double)N_SEGMENTS; - int i; - - s = SAMPLE (x1, x2); - - for (i = 1; i < N_SEGMENTS; i += 2) - { - double a1 = x1 + h * i; - double a2 = x2 + h * i; - - s += 2 * SAMPLE (a1, a2); - - if (i >= 2 && i < N_SEGMENTS - 1) - s += 4 * SAMPLE (a1, a2); - } - - s += SAMPLE (x1 + width, x2 + width); - - return h * s * (1.0 / 3.0); - } -} - -static pixman_fixed_t * -create_1d_filter (int *width, - pixman_kernel_t reconstruct, - pixman_kernel_t sample, - double scale, - int n_phases) -{ - pixman_fixed_t *params, *p; - double step; - double size; - int i; - - size = scale * filters[sample].width + filters[reconstruct].width; - *width = ceil (size); - - p = params = malloc (*width * n_phases * sizeof (pixman_fixed_t)); - if (!params) - return NULL; - - step = 1.0 / n_phases; - - for (i = 0; i < n_phases; ++i) - { - double frac = step / 2.0 + i * step; - pixman_fixed_t new_total; - int x, x1, x2; - double total; - - /* Sample convolution of reconstruction and sampling - * filter. See rounding.txt regarding the rounding - * and sample positions. - */ - - x1 = ceil (frac - *width / 2.0 - 0.5); - x2 = x1 + *width; - - total = 0; - for (x = x1; x < x2; ++x) - { - double pos = x + 0.5 - frac; - double rlow = - filters[reconstruct].width / 2.0; - double rhigh = rlow + filters[reconstruct].width; - double slow = pos - scale * filters[sample].width / 2.0; - double shigh = slow + scale * filters[sample].width; - double c = 0.0; - double ilow, ihigh; - - if (rhigh >= slow && rlow <= shigh) - { - ilow = MAX (slow, rlow); - ihigh = MIN (shigh, rhigh); - - c = integral (reconstruct, ilow, - sample, 1.0 / scale, ilow - pos, - ihigh - ilow); - } - - total += c; - *p++ = (pixman_fixed_t)(c * 65536.0 + 0.5); - } - - /* Normalize */ - p -= *width; - total = 1 / total; - new_total = 0; - for (x = x1; x < x2; ++x) - { - pixman_fixed_t t = (*p) * total + 0.5; - - new_total += t; - *p++ = t; - } - - if (new_total != pixman_fixed_1) - *(p - *width / 2) += (pixman_fixed_1 - new_total); - } - - return params; -} - -/* Create the parameter list for a SEPARABLE_CONVOLUTION filter - * with the given kernels and scale parameters - */ -PIXMAN_EXPORT pixman_fixed_t * -pixman_filter_create_separable_convolution (int *n_values, - pixman_fixed_t scale_x, - pixman_fixed_t scale_y, - pixman_kernel_t reconstruct_x, - pixman_kernel_t reconstruct_y, - pixman_kernel_t sample_x, - pixman_kernel_t sample_y, - int subsample_bits_x, - int subsample_bits_y) -{ - double sx = fabs (pixman_fixed_to_double (scale_x)); - double sy = fabs (pixman_fixed_to_double (scale_y)); - pixman_fixed_t *horz = NULL, *vert = NULL, *params = NULL; - int subsample_x, subsample_y; - int width, height; - - subsample_x = (1 << subsample_bits_x); - subsample_y = (1 << subsample_bits_y); - - horz = create_1d_filter (&width, reconstruct_x, sample_x, sx, subsample_x); - vert = create_1d_filter (&height, reconstruct_y, sample_y, sy, subsample_y); - - if (!horz || !vert) - goto out; - - *n_values = 4 + width * subsample_x + height * subsample_y; - - params = malloc (*n_values * sizeof (pixman_fixed_t)); - if (!params) - goto out; - - params[0] = pixman_int_to_fixed (width); - params[1] = pixman_int_to_fixed (height); - params[2] = pixman_int_to_fixed (subsample_bits_x); - params[3] = pixman_int_to_fixed (subsample_bits_y); - - memcpy (params + 4, horz, - width * subsample_x * sizeof (pixman_fixed_t)); - memcpy (params + 4 + width * subsample_x, vert, - height * subsample_y * sizeof (pixman_fixed_t)); - -out: - free (horz); - free (vert); - - return params; -} |