1 files changed, 119 insertions, 0 deletions
diff --git a/src/mesa/swrast/s_chan.h b/src/mesa/swrast/s_chan.h
new file mode 100644
index 00000000000..94ac8b65be1
--- /dev/null
+++ b/src/mesa/swrast/s_chan.h
@@ -0,0 +1,119 @@
+/*
+ * Mesa 3-D graphics library
+ *
+ * Copyright (C) 2011  VMware, Inc.  All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * Types, macros, etc for the GLchan datatype.
+ * The swrast module is kind of hard-coded for 8bpp color channels but
+ * may be recompiled to use 16- or 32-bit color channels.  But that
+ * feature is seldom used and is likely broken in various ways.
+ */
+
+#ifndef U_CHAN_H
+#define U_CHAN_H
+
+
+#include "main/config.h"
+
+
+/**
+ * Color channel data type.
+ */
+#if CHAN_BITS == 8
+   typedef GLubyte GLchan;
+#define CHAN_MAX 255
+#define CHAN_MAXF 255.0F
+#define CHAN_TYPE GL_UNSIGNED_BYTE
+#elif CHAN_BITS == 16
+   typedef GLushort GLchan;
+#define CHAN_MAX 65535
+#define CHAN_MAXF 65535.0F
+#define CHAN_TYPE GL_UNSIGNED_SHORT
+#elif CHAN_BITS == 32
+   typedef GLfloat GLchan;
+#define CHAN_MAX 1.0
+#define CHAN_MAXF 1.0F
+#define CHAN_TYPE GL_FLOAT
+#else
+#error "illegal number of color channel bits"
+#endif
+
+
+#if CHAN_BITS == 8
+
+#define CHAN_TO_UBYTE(c)  (c)
+#define CHAN_TO_USHORT(c) (((c) << 8) | (c))
+#define CHAN_TO_SHORT(c)  (((c) << 7) | ((c) >> 1))
+#define CHAN_TO_FLOAT(c)  UBYTE_TO_FLOAT(c)
+
+#define CLAMPED_FLOAT_TO_CHAN(c, f)    CLAMPED_FLOAT_TO_UBYTE(c, f)
+#define UNCLAMPED_FLOAT_TO_CHAN(c, f)  UNCLAMPED_FLOAT_TO_UBYTE(c, f)
+
+#define COPY_CHAN4(DST, SRC)  COPY_4UBV(DST, SRC)
+
+#elif CHAN_BITS == 16
+
+#define CHAN_TO_UBYTE(c)  ((c) >> 8)
+#define CHAN_TO_USHORT(c) (c)
+#define CHAN_TO_SHORT(c)  ((c) >> 1)
+#define CHAN_TO_FLOAT(c)  ((GLfloat) ((c) * (1.0 / CHAN_MAXF)))
+
+#define CLAMPED_FLOAT_TO_CHAN(c, f)    CLAMPED_FLOAT_TO_USHORT(c, f)
+#define UNCLAMPED_FLOAT_TO_CHAN(c, f)  UNCLAMPED_FLOAT_TO_USHORT(c, f)
+
+#define COPY_CHAN4(DST, SRC)  COPY_4V(DST, SRC)
+
+#elif CHAN_BITS == 32
+
+#define CHAN_TO_UBYTE(c)  FLOAT_TO_UBYTE(c)
+#define CHAN_TO_USHORT(c) ((GLushort) (CLAMP((c), 0.0f, 1.0f) * 65535.0))
+#define CHAN_TO_SHORT(c)  ((GLshort) (CLAMP((c), 0.0f, 1.0f) * 32767.0))
+#define CHAN_TO_FLOAT(c)  (c)
+
+#define CLAMPED_FLOAT_TO_CHAN(c, f)  c = (f)
+#define UNCLAMPED_FLOAT_TO_CHAN(c, f)      c = (f)
+
+#define COPY_CHAN4(DST, SRC)  COPY_4V(DST, SRC)
+
+#else
+
+#error unexpected CHAN_BITS size
+
+#endif
+
+
+/**
+ * Convert 4 floats to GLchan values.
+ * \param dst pointer to destination GLchan[4] array.
+ * \param f pointer to source GLfloat[4] array.
+ */
+#define UNCLAMPED_FLOAT_TO_RGBA_CHAN(dst, f)	\
+do {						\
+   UNCLAMPED_FLOAT_TO_CHAN((dst)[0], (f)[0]);	\
+   UNCLAMPED_FLOAT_TO_CHAN((dst)[1], (f)[1]);	\
+   UNCLAMPED_FLOAT_TO_CHAN((dst)[2], (f)[2]);	\
+   UNCLAMPED_FLOAT_TO_CHAN((dst)[3], (f)[3]);	\
+} while (0)
+
+
+
+#endif /* U_CHAN_H */