1 files changed, 94 insertions, 0 deletions
diff --git a/gfx/src/nsColor.h b/gfx/src/nsColor.h
new file mode 100644
index 0000000000..e47f5a4575
--- /dev/null
+++ b/gfx/src/nsColor.h
@@ -0,0 +1,94 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsColor_h___
+#define nsColor_h___
+
+#include <stdint.h>   // for uint8_t, uint32_t
+#include "nsCoord.h"  // for NSToIntRound
+#include "nsStringFwd.h"
+
+// A color is a 32 bit unsigned integer with four components: R, G, B
+// and A.
+typedef uint32_t nscolor;
+
+// Make a color out of r,g,b values. This assumes that the r,g,b values are
+// properly constrained to 0-255. This also assumes that a is 255.
+#define NS_RGB(_r, _g, _b) \
+  ((nscolor)((255 << 24) | ((_b) << 16) | ((_g) << 8) | (_r)))
+
+// Make a color out of r,g,b,a values. This assumes that the r,g,b,a
+// values are properly constrained to 0-255.
+#define NS_RGBA(_r, _g, _b, _a) \
+  ((nscolor)(((_a) << 24) | ((_b) << 16) | ((_g) << 8) | (_r)))
+
+// Extract color components from nscolor
+#define NS_GET_R(_rgba) ((uint8_t)((_rgba)&0xff))
+#define NS_GET_G(_rgba) ((uint8_t)(((_rgba) >> 8) & 0xff))
+#define NS_GET_B(_rgba) ((uint8_t)(((_rgba) >> 16) & 0xff))
+#define NS_GET_A(_rgba) ((uint8_t)(((_rgba) >> 24) & 0xff))
+
+namespace mozilla {
+
+template <typename T>
+inline uint8_t ClampColor(T aColor) {
+  if (aColor >= 255) {
+    return 255;
+  }
+  if (aColor <= 0) {
+    return 0;
+  }
+  return NSToIntRound(aColor);
+}
+
+}  // namespace mozilla
+
+enum class nsHexColorType : uint8_t {
+  NoAlpha,     // 3 or 6 digit hex colors only
+  AllowAlpha,  // 3, 4, 6, or 8 digit hex colors
+};
+
+// Translate a hex string to a color. Return true if it parses ok,
+// otherwise return false.
+// This accepts the number of digits specified by aType.
+bool NS_HexToRGBA(const nsAString& aBuf, nsHexColorType aType,
+                  nscolor* aResult);
+
+// Compose one NS_RGB color onto another. The result is what
+// you get if you draw aFG on top of aBG with operator OVER.
+nscolor NS_ComposeColors(nscolor aBG, nscolor aFG);
+
+namespace mozilla {
+
+inline uint32_t RoundingDivideBy255(uint32_t n) {
+  // There is an approximate alternative: ((n << 8) + n + 32896) >> 16
+  // But that is actually slower than this simple expression on a modern
+  // machine with a modern compiler.
+  return (n + 127) / 255;
+}
+
+}  // namespace mozilla
+
+// Translate a hex string to a color. Return true if it parses ok,
+// otherwise return false.
+// This version accepts 1 to 9 digits (missing digits are 0)
+bool NS_LooseHexToRGB(const nsString& aBuf, nscolor* aResult);
+
+// There is no function to translate a color to a hex string, because
+// the hex-string syntax does not support transparency.
+
+// Translate a color name to a color. Return true if it parses ok,
+// otherwise return false.
+bool NS_ColorNameToRGB(const nsAString& aBuf, nscolor* aResult);
+
+// Return a color name for the given nscolor.  If there is no color
+// name for it, returns null.  If there are multiple possible color
+// names for the given color, the first one in nsColorNameList.h
+// (which is generally the first one in alphabetical order) will be
+// returned.
+const char* NS_RGBToColorName(nscolor aColor);
+
+#endif /* nsColor_h___ */