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 static pixman_color_t *color_rgb888(pixman_color_t *tmp,
   9         uint8_t r, uint8_t g, uint8_t b);
  10
  11 pixman_image_t *
  12 pixman_image_from_buffer(struct ds_buffer *buffer,
  13         enum ds_buffer_data_ptr_access_flag access_flag)
  14 {
  15     pixman_image_t *image;
  16     void *data;
  17     uint32_t format;
  18     size_t stride;
  19     int width, height;
  20
  21     ds_buffer_get_size(buffer, &width, &height);
  22
  23     if (!ds_buffer_begin_data_ptr_access(buffer,
  24                 access_flag, &data, &format, &stride))
  25         return NULL;
  26
  27     format = convert_drm_format_to_pixman(format);
  28     image = pixman_image_create_bits(format, width, height, data, stride);
  29     if (!image) {
  30         ds_buffer_end_data_ptr_access(buffer);
  31         return NULL;
  32     }
  33
  34     pixman_image_set_destroy_function(image,
  35             destroy_pixman_image, ds_buffer_lock(buffer));
  36
  37     return image;
  38 }
  39
  40
  41 void
  42 pixman_image_fill_color(pixman_image_t *image, uint8_t r, uint8_t g, uint8_t b)
  43 {
  44     pixman_image_t *color_image;
  45     pixman_color_t color;
  46
  47     color_rgb888(&color, r, g, b);
  48     color_image = pixman_image_create_solid_fill(&color);
  49     pixman_image_composite32(PIXMAN_OP_SRC,
  50             color_image,
  51             NULL,
  52             image,
  53             0, 0, 0, 0, 0, 0,
  54             pixman_image_get_width(image),
  55             pixman_image_get_height(image));
  56     pixman_image_unref(color_image);
  57 }
  58
  59 static pixman_color_t *
  60 color_rgb888(pixman_color_t *tmp, uint8_t r, uint8_t g, uint8_t b)
  61 {
  62     tmp->alpha = 65535;
  63     tmp->red = (r << 8) + r;
  64     tmp->green = (g << 8) + g;
  65     tmp->blue = (b << 8) +b;
  66
  67     return tmp;
  68 }
  69
  70 static uint32_t
  71 convert_drm_format_to_pixman(uint32_t fmt)
  72 {
  73     switch (fmt) {
  74         case DRM_FORMAT_XRGB8888:
  75             return PIXMAN_x8r8g8b8;
  76         case DRM_FORMAT_ARGB8888:
  77             return PIXMAN_a8r8g8b8;
  78         default:
  79             assert(0 && "not reached");
  80     }
  81 }
  82
  83 static void
  84 destroy_pixman_image(pixman_image_t *image, void *data)
  85 {
  86     struct ds_buffer *buffer = data;
  87     ds_buffer_end_data_ptr_access(buffer);
  88     ds_buffer_unlock(buffer);
  89 }