1 files changed, 58 insertions, 0 deletions
diff --git a/src/gui/rgba.hpp b/src/gui/rgba.hpp
new file mode 100644
index 00000000..8648aece
--- /dev/null
+++ b/src/gui/rgba.hpp
@@ -0,0 +1,58 @@
+/*
+  This file is part of Ingen.
+  Copyright 2007-2016 David Robillard <http://drobilla.net/>
+
+  Ingen is free software: you can redistribute it and/or modify it under the
+  terms of the GNU Affero General Public License as published by the Free
+  Software Foundation, either version 3 of the License, or any later version.
+
+  Ingen is distributed in the hope that it will be useful, but WITHOUT ANY
+  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+  A PARTICULAR PURPOSE.  See the GNU Affero General Public License for details.
+
+  You should have received a copy of the GNU Affero General Public License
+  along with Ingen.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#ifndef INGEN_GUI_RGBA_HPP
+#define INGEN_GUI_RGBA_HPP
+
+#include <math.h>
+
+namespace Ingen {
+namespace GUI {
+
+static inline uint32_t
+rgba_to_uint(uint8_t r, uint8_t g, uint8_t b, uint8_t a)
+{
+	return ((((uint32_t)(r)) << 24) |
+	        (((uint32_t)(g)) << 16) |
+	        (((uint32_t)(b)) << 8) |
+	        (((uint32_t)(a))));
+}
+
+static inline uint8_t
+mono_interpolate(uint8_t v1, uint8_t v2, float f)
+{
+	return ((int)rint((v2) * (f) + (v1) * (1 - (f))));
+}
+
+#define RGBA_R(x) (((uint32_t)(x)) >> 24)
+#define RGBA_G(x) ((((uint32_t)(x)) >> 16) & 0xFF)
+#define RGBA_B(x) ((((uint32_t)(x)) >> 8) & 0xFF)
+#define RGBA_A(x) (((uint32_t)(x)) & 0xFF)
+
+static inline uint32_t
+rgba_interpolate(uint32_t c1, uint32_t c2, float f)
+{
+	return rgba_to_uint(
+		mono_interpolate(RGBA_R(c1), RGBA_R(c2), f),
+		mono_interpolate(RGBA_G(c1), RGBA_G(c2), f),
+		mono_interpolate(RGBA_B(c1), RGBA_B(c2), f),
+		mono_interpolate(RGBA_A(c1), RGBA_A(c2), f));
+}
+
+} // namespace GUI
+} // namespace Ingen
+
+#endif // INGEN_GUI_RGBA_HPP