Implement a generic matrix transform image filter.

This will be used in Blink to accommodate matrices that contain
rotation or shearing. This is a generalization of SkResizeImageFilter,
so I've replaced all uses of SkResizeImageFilter in Skia. (It might be
easier to review by diffing it with SkResizeImageFilter, too.)

R=reed@google.com

Review URL: https://codereview.chromium.org/211103006

git-svn-id: http://skia.googlecode.com/svn/trunk@13941 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 58 insertions, 0 deletions

diff --git a/include/effects/SkMatrixImageFilter.h b/include/effects/SkMatrixImageFilter.h
new file mode 100644
index 0000000000..004c6ef9ed
--- /dev/null
+++ b/include/effects/SkMatrixImageFilter.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright 2014 The Android Open Source Project
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkMatrixImageFilter_DEFINED
+#define SkMatrixImageFilter_DEFINED
+
+#include "SkImageFilter.h"
+#include "SkScalar.h"
+#include "SkSize.h"
+#include "SkPoint.h"
+#include "SkPaint.h"
+
+/*! \class SkMatrixImageFilter
+    Matrix transformation image filter.  This filter draws its source
+    input transformed by the given matrix.
+ */
+
+class SK_API SkMatrixImageFilter : public SkImageFilter {
+public:
+    /** Construct a 2D transformation image filter.
+     *  @param transform    The matrix to apply when drawing the src bitmap
+     *  @param filterLevel  The quality of filtering to apply when scaling.
+     *  @param input        The input image filter.  If NULL, the src bitmap
+     *                      passed to filterImage() is used instead.
+     */
+
+    static SkMatrixImageFilter* Create(const SkMatrix& transform,
+                                       SkPaint::FilterLevel,
+                                       SkImageFilter* input = NULL);
+    virtual ~SkMatrixImageFilter();
+
+    virtual void computeFastBounds(const SkRect&, SkRect*) const SK_OVERRIDE;
+
+    SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkMatrixImageFilter)
+
+protected:
+    SkMatrixImageFilter(const SkMatrix& transform,
+                        SkPaint::FilterLevel,
+                        SkImageFilter* input = NULL);
+    SkMatrixImageFilter(SkReadBuffer& buffer);
+    virtual void flatten(SkWriteBuffer&) const SK_OVERRIDE;
+
+    virtual bool onFilterImage(Proxy*, const SkBitmap& src, const Context&,
+                               SkBitmap* result, SkIPoint* loc) const SK_OVERRIDE;
+    virtual bool onFilterBounds(const SkIRect& src, const SkMatrix&,
+                                SkIRect* dst) const SK_OVERRIDE;
+
+private:
+    SkMatrix              fTransform;
+    SkPaint::FilterLevel  fFilterLevel;
+    typedef SkImageFilter INHERITED;
+};
+
+#endif