privatization of SkPerspIter.h

remove obsolete SkRelay.h



git-svn-id: http://skia.googlecode.com/svn/trunk@5025 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 48 insertions, 0 deletions

diff --git a/src/core/SkPerspIter.h b/src/core/SkPerspIter.h
new file mode 100644
index 0000000000..7f6add289c
--- /dev/null
+++ b/src/core/SkPerspIter.h
@@ -0,0 +1,48 @@
+
+/*
+ * Copyright 2006 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 SkPerspIter_DEFINED
+#define SkPerspIter_DEFINED
+
+#include "SkMatrix.h"
+
+class SkPerspIter {
+public:
+    /** Iterate a line through the matrix [x,y] ... [x+count-1, y].
+        @param m    The matrix we will be iterating a line through
+        @param x    The initial X coordinate to be mapped through the matrix
+        @param y    The initial Y coordinate to be mapped through the matrix
+        @param count The number of points (x,y) (x+1,y) (x+2,y) ... we will eventually map
+    */
+    SkPerspIter(const SkMatrix& m, SkScalar x, SkScalar y, int count);
+    
+    /** Return the buffer of [x,y] fixed point values we will be filling.
+        This always returns the same value, so it can be saved across calls to
+        next().
+    */
+    const SkFixed* getXY() const { return fStorage; }
+
+    /** Return the number of [x,y] pairs that have been filled in the getXY() buffer.
+        When this returns 0, the iterator is finished.
+    */
+    int next();
+    
+private:
+    enum {
+        kShift  = 4,
+        kCount  = (1 << kShift)
+    };
+    const SkMatrix& fMatrix;
+    SkFixed         fStorage[kCount * 2];
+    SkFixed         fX, fY;
+    SkScalar        fSX, fSY;
+    int             fCount;
+};
+
+#endif