mirror of
https://salsa.debian.org/xorg-team/lib/pixman
synced 2025-09-01 10:35:16 +00:00
85b390cadf
According to the RENDER spec, the origin of the alpha map is interpreted relative to the origin of the drawable of the image, not the origin of the drawable of the alpha map. This commit fixes that and adds an alpha-test.c test program. The only use of alpha maps I have been able to find is in Qt and they don't use a non-zero alpha origin.
118 lines
3.4 KiB
C
118 lines
3.4 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include "pixman.h"
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#include "utils.h"
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int
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main (int argc, char **argv)
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{
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#define WIDTH 400
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#define HEIGHT 200
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uint32_t *alpha = malloc (WIDTH * HEIGHT * 4);
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uint32_t *dest = malloc (WIDTH * HEIGHT * 4);
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uint32_t *src = malloc (WIDTH * HEIGHT * 4);
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pixman_image_t *grad_img;
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pixman_image_t *alpha_img;
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pixman_image_t *solid_img;
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pixman_image_t *dest_img;
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pixman_image_t *src_img;
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int i;
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pixman_gradient_stop_t stops[2] =
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{
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{ pixman_int_to_fixed (0), { 0x0000, 0x0000, 0x0000, 0x0000 } },
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{ pixman_int_to_fixed (1), { 0xffff, 0x0000, 0x1111, 0xffff } }
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};
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pixman_point_fixed_t p1 = { pixman_double_to_fixed (0), 0 };
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pixman_point_fixed_t p2 = { pixman_double_to_fixed (WIDTH),
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pixman_int_to_fixed (0) };
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pixman_transform_t trans = {
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{ { pixman_double_to_fixed (2), pixman_double_to_fixed (0.5), pixman_double_to_fixed (-100), },
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{ pixman_double_to_fixed (0), pixman_double_to_fixed (3), pixman_double_to_fixed (0), },
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{ pixman_double_to_fixed (0), pixman_double_to_fixed (0.000), pixman_double_to_fixed (1.0) }
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}
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};
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pixman_transform_t id = {
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{ { pixman_fixed_1, 0, 0 },
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{ 0, pixman_fixed_1, 0 },
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{ 0, 0, pixman_fixed_1 } }
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};
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pixman_point_fixed_t c_inner;
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pixman_point_fixed_t c_outer;
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pixman_fixed_t r_inner;
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pixman_fixed_t r_outer;
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pixman_color_t red = { 0xffff, 0x0000, 0x0000, 0xffff };
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for (i = 0; i < WIDTH * HEIGHT; ++i)
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alpha[i] = 0x4f00004f; /* pale blue */
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alpha_img = pixman_image_create_bits (PIXMAN_a8r8g8b8,
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WIDTH, HEIGHT,
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alpha,
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WIDTH * 4);
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for (i = 0; i < WIDTH * HEIGHT; ++i)
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dest[i] = 0xffffff00; /* yellow */
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dest_img = pixman_image_create_bits (PIXMAN_a8r8g8b8,
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WIDTH, HEIGHT,
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dest,
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WIDTH * 4);
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for (i = 0; i < WIDTH * HEIGHT; ++i)
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src[i] = 0xffff0000;
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src_img = pixman_image_create_bits (PIXMAN_a8r8g8b8,
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WIDTH, HEIGHT,
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src,
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WIDTH * 4);
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c_inner.x = pixman_double_to_fixed (50.0);
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c_inner.y = pixman_double_to_fixed (50.0);
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c_outer.x = pixman_double_to_fixed (50.0);
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c_outer.y = pixman_double_to_fixed (50.0);
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r_inner = 0;
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r_outer = pixman_double_to_fixed (50.0);
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#if 0
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grad_img = pixman_image_create_conical_gradient (&c_inner, r_inner,
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stops, 2);
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#endif
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#if 0
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grad_img = pixman_image_create_conical_gradient (&c_inner, r_inner,
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stops, 2);
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grad_img = pixman_image_create_linear_gradient (&c_inner, &c_outer,
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r_inner, r_outer,
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stops, 2);
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#endif
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grad_img = pixman_image_create_linear_gradient (&p1, &p2,
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stops, 2);
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pixman_image_set_transform (grad_img, &id);
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pixman_image_set_repeat (grad_img, PIXMAN_REPEAT_PAD);
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pixman_image_composite (PIXMAN_OP_OVER, grad_img, NULL, alpha_img,
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0, 0, 0, 0, 0, 0, 10 * WIDTH, HEIGHT);
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pixman_image_set_alpha_map (src_img, alpha_img, 10, 10);
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pixman_image_composite (PIXMAN_OP_OVER, src_img, NULL, dest_img,
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0, 0, 0, 0, 0, 0, 10 * WIDTH, HEIGHT);
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printf ("0, 0: %x\n", dest[0]);
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printf ("10, 10: %x\n", dest[10 * 10 + 10]);
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printf ("w, h: %x\n", dest[(HEIGHT - 1) * 100 + (WIDTH - 1)]);
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show_image (dest_img);
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pixman_image_unref (src_img);
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pixman_image_unref (grad_img);
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pixman_image_unref (alpha_img);
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free (dest);
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return 0;
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}
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