lib: Add a helper to paint a PNG using cairo

Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>

diff --git a/lib/drmtest.c b/lib/drmtest.c
index 7f89fd1..d9749d7 100644 (file)
--- a/lib/drmtest.c
+++ b/lib/drmtest.c
@@ -1475,6 +1475,34 @@ void kmstest_paint_test_pattern(cairo_t *cr, int width, int height)
        assert(!cairo_status(cr));
 }
 
+void kmstest_paint_image(cairo_t *cr, const char *filename,
+                        int dst_x, int dst_y, int dst_width, int dst_height)
+{
+       cairo_surface_t *image;
+       int img_width, img_height;
+       double scale_x, scale_y;
+
+       image = cairo_image_surface_create_from_png(filename);
+       assert(cairo_surface_status(image) == CAIRO_STATUS_SUCCESS);
+
+       img_width = cairo_image_surface_get_width(image);
+       img_height = cairo_image_surface_get_height(image);
+
+       scale_x = (double)dst_width / img_width;
+       scale_y = (double)dst_height / img_height;
+
+       cairo_save(cr);
+
+       cairo_translate(cr, dst_x, dst_y);
+       cairo_scale(cr, scale_x, scale_y);
+       cairo_set_source_surface(cr, image, 0, 0);
+       cairo_paint(cr);
+
+       cairo_surface_destroy(image);
+
+       cairo_restore(cr);
+}
+
 #define DF(did, cid, _bpp, _depth)     \
        { DRM_FORMAT_##did, CAIRO_FORMAT_##cid, # did, _bpp, _depth }
 static struct format_desc_struct {

diff --git a/lib/drmtest.h b/lib/drmtest.h
index 35796ca..b0b353f 100644 (file)
--- a/lib/drmtest.h
+++ b/lib/drmtest.h
@@ -355,6 +355,8 @@ cairo_t *kmstest_get_cairo_ctx(int fd, struct kmstest_fb *fb);
 void kmstest_paint_color_gradient(cairo_t *cr, int x, int y, int w, int h,
                                  int r, int g, int b);
 void kmstest_paint_test_pattern(cairo_t *cr, int width, int height);
+void kmstest_paint_image(cairo_t *cr, const char *filename,
+                        int dst_x, int dst_y, int dst_width, int dst_height);
 void kmstest_dump_mode(drmModeModeInfo *mode);
 int kmstest_get_pipe_from_crtc_id(int fd, int crtc_id);
 const char *kmstest_format_str(uint32_t drm_format);