1 /*
2  * Copyright 2013 Google Inc.
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 #ifndef SkMatrixUtils_DEFINED
9 #define SkMatrixUtils_DEFINED
10 
11 #include "SkPoint.h"
12 #include "SkSize.h"
13 
14 class SkMatrix;
15 class SkPaint;
16 
17 /**
18  *  Given a matrix, size and paint, return true if the computed dst-rect would
19  *  align such that there is a 1-to-1 coorspondence between src and dst pixels.
20  *  This can be called by drawing code to see if drawBitmap can be turned into
21  *  drawSprite (which is faster).
22  *
23  *  The src-rect is defined to be { 0, 0, size.width(), size.height() }
24  */
25 bool SkTreatAsSprite(const SkMatrix&, const SkISize& size, const SkPaint& paint);
26 
27 /** Decomposes the upper-left 2x2 of the matrix into a rotation (represented by
28     the cosine and sine of the rotation angle), followed by a non-uniform scale,
29     followed by another rotation. If there is a reflection, one of the scale
30     factors will be negative.
31     Returns true if successful. Returns false if the matrix is degenerate.
32     */
33 bool SkDecomposeUpper2x2(const SkMatrix& matrix,
34                          SkPoint* rotation1,
35                          SkPoint* scale,
36                          SkPoint* rotation2);
37 
38 #endif
39