examples/pixman-helper.c

   1 #include "pixman-helper.h"
   2
   3 #include <assert.h>
   4 #include <drm_fourcc.h>
   5
   6 static void destroy_pixman_image(pixman_image_t *image, void *data);
   7 static uint32_t convert_drm_format_to_pixman(uint32_t fmt);
   8
   9 pixman_image_t *
  10 pixman_image_from_buffer(struct ds_buffer *buffer,
  11         enum ds_buffer_data_ptr_access_flag access_flag)
  12 {
  13     pixman_image_t *image;
  14     void *data;
  15     uint32_t format;
  16     size_t stride;
  17     int width, height;
  18
  19     ds_buffer_get_size(buffer, &width, &height);
  20
  21     if (!ds_buffer_begin_data_ptr_access(buffer,
  22                 access_flag, &data, &format, &stride))
  23         return NULL;
  24
  25     format = convert_drm_format_to_pixman(format);
  26     image = pixman_image_create_bits(format, width, height, data, stride);
  27     if (!image) {
  28         ds_buffer_end_data_ptr_access(buffer);
  29         return NULL;
  30     }
  31
  32     pixman_image_set_destroy_function(image,
  33             destroy_pixman_image, ds_buffer_lock(buffer));
  34
  35     return image;
  36 }
  37
  38 void
  39 pixman_image_fill_color(pixman_image_t *image, uint8_t r, uint8_t g, uint8_t b)
  40 {
  41     pixman_image_t *color_image;
  42     pixman_color_t color;
  43
  44     color_rgb888(&color, r, g, b);
  45     color_image = pixman_image_create_solid_fill(&color);
  46     pixman_image_composite32(PIXMAN_OP_SRC,
  47             color_image,
  48             NULL,
  49             image,
  50             0, 0, 0, 0, 0, 0,
  51             pixman_image_get_width(image),
  52             pixman_image_get_height(image));
  53     pixman_image_unref(color_image);
  54 }
  55
  56 pixman_color_t *
  57 color_rgb888(pixman_color_t *tmp, uint8_t r, uint8_t g, uint8_t b)
  58 {
  59     tmp->alpha = 65535;
  60     tmp->red = (r << 8) + r;
  61     tmp->green = (g << 8) + g;
  62     tmp->blue = (b << 8) +b;
  63
  64     return tmp;
  65 }
  66
  67 static uint32_t
  68 convert_drm_format_to_pixman(uint32_t fmt)
  69 {
  70     switch (fmt) {
  71         case DRM_FORMAT_XRGB8888:
  72             return PIXMAN_x8r8g8b8;
  73         case DRM_FORMAT_ARGB8888:
  74             return PIXMAN_a8r8g8b8;
  75         default:
  76             assert(0 && "not reached");
  77     }
  78 }
  79
  80 static void
  81 destroy_pixman_image(pixman_image_t *image, void *data)
  82 {
  83     struct ds_buffer *buffer = data;
  84     ds_buffer_end_data_ptr_access(buffer);
  85     ds_buffer_unlock(buffer);
  86 }