Enable flattening and unflattening of SkColorSpace

include/core/SkMatrix44.h

Index: include/core/SkMatrix44.h
diff --git a/include/core/SkMatrix44.h b/include/core/SkMatrix44.h
index d64d4b7074055e489ed673ffa75c31bc9d869bf7..bcf7a03760526b1ef9f648b5810e7985746cda95 100644
--- a/include/core/SkMatrix44.h
+++ b/include/core/SkMatrix44.h
@@ -287,6 +287,11 @@ public:
     void asRowMajorf(float[]) const;
     void asRowMajord(double[]) const;
 
+    /** Efficiently reads 12 matrix entries, ignoring the last col.
+     *  This is typically useful when we know the last col is (0, 0, 0, 1).
+     */
+    void as4x3ColMajorf(float[]) const;
+
     /** These methods allow one to efficiently set all matrix entries from an
      *  array. The given array must have room for exactly 16 entries. Whenever
      *  possible, they will try to use memcpy rather than an entry-by-entry
@@ -312,6 +317,10 @@ public:
                 SkMScalar m20, SkMScalar m21, SkMScalar m22);
     void set3x3ColMajorf(const float[]);
 
+    /* This sets the top-left of the matrix and clears the
+     * perspective components (with [3][3] set to 1). */

[reed1, 2016/06/21 20:45:01]

Lets make these private helpers at first. Not sure this should be a public
helper yet.

[msarett, 2016/06/21 21:47:45]

sgtm, done.

+    void set4x3ColMajorf(const float[]);
+
     void setTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
     void preTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
     void postTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);