1 files changed, 41 insertions, 0 deletions
diff --git a/gfx/skia/skia/include/effects/SkTableMaskFilter.h b/gfx/skia/skia/include/effects/SkTableMaskFilter.h
new file mode 100644
index 0000000000..412f138353
--- /dev/null
+++ b/gfx/skia/skia/include/effects/SkTableMaskFilter.h
@@ -0,0 +1,41 @@
+/*
+ * 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 SkTableMaskFilter_DEFINED
+#define SkTableMaskFilter_DEFINED
+
+#include "include/core/SkScalar.h"
+#include "include/core/SkTypes.h"
+
+#include <cstdint>
+
+class SkMaskFilter;
+
+/** \class SkTableMaskFilter
+
+    Applies a table lookup on each of the alpha values in the mask.
+    Helper methods create some common tables (e.g. gamma, clipping)
+ */
+class SK_API SkTableMaskFilter {
+public:
+    /** Utility that sets the gamma table
+     */
+    static void MakeGammaTable(uint8_t table[256], SkScalar gamma);
+
+    /** Utility that creates a clipping table: clamps values below min to 0
+        and above max to 255, and rescales the remaining into 0..255
+     */
+    static void MakeClipTable(uint8_t table[256], uint8_t min, uint8_t max);
+
+    static SkMaskFilter* Create(const uint8_t table[256]);
+    static SkMaskFilter* CreateGamma(SkScalar gamma);
+    static SkMaskFilter* CreateClip(uint8_t min, uint8_t max);
+
+    SkTableMaskFilter() = delete;
+};
+
+#endif