WarpBlt is a little warp-drive added on to BitBlt. It takes a quadrilateral as its source specification, while its destination is traversed and combined just like any other call to copyBits.

The source quadrilateral is specified as an array of points starting with the corner that wants to end up in the topLeft, and proceding to the successive points that want to follow CCW around the destination rectangle. Note that in specifying a plain old rectangle source, its non topLeft points must be actual pixels, not outside by 1, as with rectangle bottmRight, eg. See the method Rectangle asQuad.

WarpBlt does a fast job of rotation, reflection and scaling, and it can even produce a semblance of perspective. Depth parameters are included for future improvements in this direction. but the primitve does not support this yet.

	setup
	cellSize cellSize:

	smoothing
	mixPix:sourceMap:destMap: rgbMap:from:to:

	system simulation
	warpBitsSimulated warpBitsSimulated:sourceMap:

	form rotation
	rotate:degrees:center:scaleBy:smoothing:

	initialization
	toForm:

	instance creation
	current

	primitives	top
	copyQuad:toRect:
	deltaFrom:to:nSteps: Utility routine for computing Warp increments. x1 is starting pixel, x2 is ending pixel; assumes n >= 1
	sourceForm:destRect: Set up a WarpBlt from the entire source Form to the given destination rectangle.
	sourceQuad:destRect:
	startFrom:to:offset: Utility routine for computing Warp increments.
	warpBits Move those pixels!
	warpBitsSmoothing:sourceMap:

	setup	top
	cellSize
	cellSize:

	smoothing	top
	mixPix:sourceMap:destMap: Average the pixels in array pix to produce a destination pixel. First average the RGB values either from the pixels directly, or as supplied in the sourceMap. Then return either the resulting RGB value directly, or use it to index the destination color map.
	rgbMap:from:to: NOTE: This code is copied verbatim from BitBltSimulation so that it may be removed from the system

	system simulation	top
	warpBitsSimulated Simulate WarpBlt
	warpBitsSimulated:sourceMap: Simulate WarpBlt

	examples	top
	test1 Display restoreAfter: [WarpBlt test1]
	test12 Display restoreAfter: [WarpBlt test12]
	test3 Display restoreAfter: [WarpBlt test3]
	test4 Display restoreAfter: [WarpBlt test4]
	test5 Display restoreAfter: [WarpBlt test5]

	form rotation	top
	rotate:degrees:center:scaleBy:smoothing: Rotate the given Form the given number of degrees about the given center and scale its width and height by x and y of the given scale point. Smooth using the given cell size, an integer between 1 and 3, where 1 means no smoothing. Return a pair where the first element is the rotated Form and the second is the position offset required to align the center of the rotated Form with that of the original. Note that the dimensions of the resulting Form generally differ from those of the original.

	initialization	top
	toForm: Default cell size is 1 (no pixel smoothing)

	instance creation	top
	current Return the class currently to be used for WarpBlt