Matrix

Object Hierarchy:

Description:

[ CCode ( cname = "cairo_matrix_t" , type_id = "cairo_gobject_matrix_get_type ()" ) ]
public struct Matrix

Example: Cartesian coordinate system (II):

public static int main (string[] args) {
	// Create a context:
	Cairo.ImageSurface surface = new Cairo.ImageSurface (Cairo.Format.ARGB32, 500, 500);
	Cairo.Context context = new Cairo.Context (surface);

	// Transformations:
	Cairo.Matrix matrix = Cairo.Matrix.identity ();
	matrix.translate (250, 250);
	matrix.scale (1, -1);

	context.set_matrix (matrix);

	// Y-Axis:
	context.move_to (-250, 0);
	context.line_to (250, 0);
	context.stroke ();

	// X-Axis:
	context.move_to (0, -250);
	context.line_to (0, 250);
	context.stroke ();

	// P (20, 10)
	context.set_source_rgba (0, 0, 0, 1);
	context.arc (20, 10, 2, 0, 2*Math.PI);
	context.fill ();

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

	return 0;
}

valac --pkg cairo cartesian-coordinate-system-matrix.vala

Namespace: Cairo

Package: cairo

Content:

Creation methods:

public Matrix (double xx, double yx, double xy, double yy, double x0, double y0)
public Matrix.identity ()

Methods:

public Status invert ()
public void multiply (Matrix a, Matrix b)
public void rotate (double radians)
public void scale (double sx, double sy)
public void transform_distance (ref double dx, ref double dy)
public void transform_point (ref double x, ref double y)
public void translate (double tx, double ty)

Fields:

public double xx
public double yx
public double xy
public double yy
public double x0
public double y0