Codea - Learn Lua for iOS Game Development - page 288

noTint
The tint function changes the color of the sprite according to the multiply effect in
image-processing packages. The noTint function removes all of the tinting while drawing
the sprites.
Transformation Functions
The display objects that we can create can be transformed in various ways, including rotating
and scaling, with functions like rotate , scale , translate , and zLevel (what a lot of developers
refer to as the z-Index) . These functions apply the respective transformations to all subsequent
drawings, not just an individual display object.
Rotate
The rotate function takes the angle arguments in degrees.
rotate(30)
rect (226,226,52,52)
Scale
The scale function takes the scaling parameters either as a single scaling factor that is applied to all
the axes, or as individual axes.
scale(amount)
scale(xScale, yScale)
scale(xScale, yScale, zScale)
Translate
The translate function specifies an amount to displace the subsequent drawings. Displacement is
like an offset that is added to the coordinates.
rect(0,0,50,50)
translate(20,20)
rect(0,0,50,50)
translate(40,40)
rect(0,0,50,50)
Note All of the transformation functions are relative, which means that they will perform the
operations of the given value from the current value. For example, rotate(10) will rotate the object
10 degrees from its current position.
Transform functions change the display matrix . The display matrix is like a stack, where the current
settings can be saved using the pushMatrix function and the original settings can be restored using
the popMatrix function. In certain cases, you can also reset the entire display matrix to its default
values using the resetMatrix function.