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#include <stdlib.h>
#include <stdio.h>
#include "pixman.h"
#include <gtk/gtk.h>
GdkPixbuf *
pixbuf_from_argb32 (uint32_t *bits,
int width,
int height,
int stride)
{
GdkPixbuf *pixbuf = gdk_pixbuf_new (GDK_COLORSPACE_RGB, TRUE,
8, width, height);
int p_stride = gdk_pixbuf_get_rowstride (pixbuf);
guint32 *p_bits = (guint32 *)gdk_pixbuf_get_pixels (pixbuf);
int w, h;
for (h = 0; h < height; ++h)
{
for (w = 0; w < width; ++w)
{
uint32_t argb = bits[h * stride + w];
guint r, g, b, a;
char *pb = p_bits;
pb += h * p_stride + w * 4;
r = (argb & 0x00ff0000) >> 16;
g = (argb & 0x0000ff00) >> 8;
b = (argb & 0x000000ff) >> 0;
a = (argb & 0xff000000) >> 24;
if (a)
{
r = (r * 255) / a;
g = (g * 255) / a;
b = (b * 255) / a;
}
pb[0] = r;
pb[1] = g;
pb[2] = b;
pb[3] = a;
}
}
return pixbuf;
}
static gboolean
on_expose (GtkWidget *widget, GdkEventExpose *expose, gpointer data)
{
GdkPixbuf *pixbuf = data;
gdk_draw_pixbuf (widget->window, NULL,
pixbuf, 0, 0, 0, 0,
gdk_pixbuf_get_width (pixbuf),
gdk_pixbuf_get_height (pixbuf),
GDK_RGB_DITHER_NONE,
0, 0);
return TRUE;
}
static void
show_window (uint32_t *bits, int w, int h, int stride)
{
GdkPixbuf *pixbuf;
GtkWidget *window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
pixbuf = pixbuf_from_argb32 (bits, w, h, stride);
g_signal_connect (window, "expose_event", G_CALLBACK (on_expose), pixbuf);
gtk_widget_show (window);
gtk_main ();
}
#define WIDTH 100
#define HEIGHT 100
static uint32_t
reader (const void *src, int size)
{
switch (size)
{
case 1:
return *(uint8_t *)src;
case 2:
return *(uint16_t *)src;
case 4:
return *(uint32_t *)src;
default:
g_assert_not_reached();
}
}
static void
writer (void *src, uint32_t value, int size)
{
switch (size)
{
case 1:
*(uint8_t *)src = value;
break;
case 2:
*(uint16_t *)src = value;
break;
case 4:
*(uint32_t *)src = value;
break;
}
}
int
main (int argc, char **argv)
{
uint32_t *src = malloc (WIDTH * HEIGHT * 4);
uint32_t *dest = malloc (WIDTH * HEIGHT * 4);
pixman_image_t *src_img;
pixman_image_t *dest_img;
int i, j;
gtk_init (&argc, &argv);
for (i = 0; i < WIDTH * HEIGHT; ++i)
src[i] = 0x7f7f0000; /* red */
for (i = 0; i < WIDTH * HEIGHT; ++i)
dest[i] = 0x7f0000ff; /* blue */
src_img = pixman_image_create_bits (PIXMAN_a8r8g8b8,
WIDTH, HEIGHT,
src,
WIDTH * 4);
dest_img = pixman_image_create_bits (PIXMAN_a8r8g8b8,
WIDTH, HEIGHT,
dest,
WIDTH * 4);
pixman_image_set_accessors (src_img, reader, writer);
pixman_image_set_accessors (dest_img, reader, writer);
pixman_image_composite (PIXMAN_OP_OVER, src_img, NULL, dest_img,
0, 0, 0, 0, 0, 0, WIDTH, HEIGHT);
#if 0
for (i = 0; i < WIDTH; ++i)
{
for (j = 0; j < HEIGHT; ++j)
g_print ("%x, ", dest[i * WIDTH + j]);
g_print ("\n");
}
#endif
show_window (dest, WIDTH, HEIGHT, WIDTH);
pixman_image_unref (src_img);
pixman_image_unref (dest_img);
free (src);
free (dest);
return 0;
}
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