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-rw-r--r--qemu/pixman/pixman/pixman-filter.c350
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
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--- a/qemu/pixman/pixman/pixman-filter.c
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@@ -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;
-}