Example: Clip regions and image surfaces

public static int main (string[] args) {
// Create a context:
Cairo.ImageSurface surface = new Cairo.ImageSurface (Cairo.Format.ARGB32, 256, 256);
Cairo.Context context = new Cairo.Context (surface);

// The arc:
context.arc (128.0, 128.0, 76.8, 0, 2*Math.PI);
context.clip ();
context.new_path (); // path not consumed by clip()

// The image:
string image_path = Path.build_filename (Path.get_dirname (args[0]) , "romedalen.png");
Cairo.ImageSurface image = new Cairo.ImageSurface.from_png (image_path);
int w = image.get_width ();
int h = image.get_height ();
context.scale (256.0/w, 256.0/h);

context.set_source_surface (image, 0, 0);
context.paint ();

// Save the image:
surface.write_to_png ("img.png");

return 0;
}

 valac --pkg cairo clip-image.vala

See:




2022 vala-language.org