Canvas Pocket Reference

Name

CRC.setTransform() — sets the transformation matrix

Synopsis

void setTransform(float a, float b,
                  float c, float d,
                  float e, float f)

Arguments

a, b, c, d, e, f

Six elements of a 3 × 3 affine transformation matrix

Description

This method allows you to set the current transformation matrix directly rather than through a series of calls to translate(), scale(), and rotate(). After calling this method, the new transformation is:

x'   a c e   x   =  ax + cy + e
y' = b d f × y   =  bx + dy + f
1    0 0 1   1

Example

You can temporarily reset the transformation of a context c to the identity transform, so that you can work with raw canvas coordinates, using code like this:

c.save();                    // Save current transform
c.setTransform(1,0,0,1,0,0); // Set identity transform
  /* Now use raw canvas coordinates here */
c.restore();                 // Revert to old transform

See Also

CRC.rotate(), CRC.scale(), CRC.transform(), CRC.translate()