Move Android shadow rendering interface to util library.

BUG=skia:6119

Change-Id: I8318cf2758042ffd0c81c5fa74240acbf7bea61f
Reviewed-on: https://skia-review.googlesource.com/6999
Commit-Queue: Jim Van Verth <jvanverth@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/include/utils/SkShadowUtils.h b/include/utils/SkShadowUtils.h
new file mode 100755
index 0000000000..c3809295fb
--- /dev/null
+++ b/include/utils/SkShadowUtils.h
@@ -0,0 +1,39 @@
+
+/*
+ * Copyright 2017 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#ifndef SkShadowUtils_DEFINED
+#define SkShadowUtils_DEFINED
+
+#include "SkColor.h"
+#include "SkScalar.h"
+
+class SkCanvas;
+class SkPath;
+
+class SkShadowUtils {
+public:
+    enum ShadowFlags {
+        kNone_ShadowFlag = 0x00,
+        /** The occluding object is not opaque. Knowing that the occluder is opaque allows
+        * us to cull shadow geometry behind it and improve performance. */
+        kTransparentOccluder_ShadowFlag = 0x01,
+        /** Use a larger umbra for a darker shadow */
+        kLargerUmbra_ShadowFlag = 0x02,
+        /** Use a Gaussian for the edge function rather than smoothstep */
+        kGaussianEdge_ShadowFlag = 0x04,
+        /** mask for all shadow flags */
+        kAll_ShadowFlag = 0x07
+    };
+
+    // Draw an offset spot shadow and outlining ambient shadow for the given path.
+    static void DrawShadow(SkCanvas*, const SkPath& path, SkScalar occluderHeight,
+                           const SkPoint3& lightPos, SkScalar lightRadius,
+                           SkScalar ambientAlpha, SkScalar spotAlpha, SkColor color,
+                           uint32_t flags = kNone_ShadowFlag);
+};
+
+#endif