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| author |  commit-bot@chromium.org <commit-bot@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> | 2013-10-04 20:38:08 +0000 |
|---|---|---|
| committer | commit-bot@chromium.org <commit-bot@chromium.org@2bbb7eff-a529-9590-31e7-b0007b416f81> | 2013-10-04 20:38:08 +0000 |
| commit | 761f860a427e9ebb088c4d1e5fba04deb29b5a6f (patch) | |
| tree | 3a90988245495b04d8bc2095a017df75c320d642 /include/utils/SkMatrix44.h | |
| parent | 6b30e457409f37c91c301cd82040e733e2930286 (diff) | |
Add perspective support to SkMatrix44 initializers.
I noticed SkMatrix <-> SkMatrix44 conversions were dropping the
perspective values on the floor. As we use SkMatrix44 heavily in
Chromium, I'm concerned this missing code will cause a bug eventually.
It should be correct to simply use the bottom row of the 4x4 matrix
excluding the third column.
BUG=
R=reed@google.com
Author: aelias@chromium.org
Review URL: https://codereview.chromium.org/25484006
git-svn-id: http://skia.googlecode.com/svn/trunk@11622 2bbb7eff-a529-9590-31e7-b0007b416f81
Diffstat (limited to 'include/utils/SkMatrix44.h')
| -rw-r--r-- | include/utils/SkMatrix44.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/include/utils/SkMatrix44.h b/include/utils/SkMatrix44.h index 6e85bb56f4..9282770588 100644 --- a/include/utils/SkMatrix44.h +++ b/include/utils/SkMatrix44.h @@ -137,6 +137,14 @@ public: return !(other == *this); } + /* When converting from SkMatrix44 to SkMatrix, the third row and + * column is dropped. When converting from SkMatrix to SkMatrix44 + * the third row and column remain as identity: + * [ a b c ] [ a b 0 c ] + * [ d e f ] -> [ d e 0 f ] + * [ g h i ] [ 0 0 1 0 ] + * [ g h 0 i ] + */ SkMatrix44(const SkMatrix&); SkMatrix44& operator=(const SkMatrix& src); operator SkMatrix() const; @@ -259,6 +267,8 @@ public: void setRowMajor(const SkMScalar data[]) { this->setRowMajord(data); } #endif + /* This sets the top-left of the matrix and clears the translation and + * perspective components (with [3][3] set to 1). */ void set3x3(SkMScalar m00, SkMScalar m01, SkMScalar m02, SkMScalar m10, SkMScalar m11, SkMScalar m12, SkMScalar m20, SkMScalar m21, SkMScalar m22); |