[Mesa-dev] [PATCH 5/6] gallium: Move sRGB <-> RGB handling to libmesautil

Jason Ekstrand jason at jlekstrand.net
Thu Jul 24 17:15:22 PDT 2014


Signed-off-by: Jason Ekstrand <jason.ekstrand at intel.com>
---
 src/gallium/Automake.inc                      |   2 +
 src/gallium/auxiliary/Makefile.am             |   4 -
 src/gallium/auxiliary/Makefile.sources        |   1 -
 src/gallium/auxiliary/SConscript              |   8 +-
 src/gallium/auxiliary/util/u_format_pack.py   |   2 +-
 src/gallium/auxiliary/util/u_format_s3tc.c    |   2 +-
 src/gallium/auxiliary/util/u_format_srgb.h    | 147 ------------------------
 src/gallium/auxiliary/util/u_format_srgb.py   | 155 --------------------------
 src/gallium/drivers/llvmpipe/SConscript       |   2 +-
 src/gallium/drivers/nouveau/Makefile.am       |   1 +
 src/gallium/drivers/nouveau/nv50/nv50_state.c |   2 +-
 src/gallium/targets/graw-gdi/SConscript       |   1 +
 src/gallium/targets/graw-null/SConscript      |   2 +-
 src/gallium/targets/graw-xlib/SConscript      |   1 +
 src/gallium/targets/pipe-loader/Makefile.am   |   2 +-
 src/gallium/tests/graw/SConscript             |   2 +-
 src/gallium/tests/unit/SConscript             |   2 +-
 src/util/Makefile.am                          |  11 +-
 src/util/Makefile.sources                     |   3 +
 src/util/SConscript                           |  12 +-
 src/util/format_srgb.h                        | 133 ++++++++++++++++++++++
 src/util/format_srgb.py                       | 155 ++++++++++++++++++++++++++
 22 files changed, 326 insertions(+), 324 deletions(-)
 delete mode 100644 src/gallium/auxiliary/util/u_format_srgb.h
 delete mode 100644 src/gallium/auxiliary/util/u_format_srgb.py
 create mode 100644 src/util/format_srgb.h
 create mode 100644 src/util/format_srgb.py

diff --git a/src/gallium/Automake.inc b/src/gallium/Automake.inc
index 22ee166..74053eb 100644
--- a/src/gallium/Automake.inc
+++ b/src/gallium/Automake.inc
@@ -11,6 +11,7 @@ GALLIUM_CFLAGS = \
 # preprocessor is determined by the ordering of the -I flags.
 GALLIUM_DRIVER_CFLAGS = \
 	-I$(srcdir)/include \
+	-I$(top_srcdir)/src \
 	-I$(top_srcdir)/include \
 	-I$(top_srcdir)/src/gallium/include \
 	-I$(top_srcdir)/src/gallium/auxiliary \
@@ -20,6 +21,7 @@ GALLIUM_DRIVER_CFLAGS = \
 
 GALLIUM_DRIVER_CXXFLAGS = \
 	-I$(srcdir)/include \
+	-I$(top_srcdir)/src \
 	-I$(top_srcdir)/include \
 	-I$(top_srcdir)/src/gallium/include \
 	-I$(top_srcdir)/src/gallium/auxiliary \
diff --git a/src/gallium/auxiliary/Makefile.am b/src/gallium/auxiliary/Makefile.am
index 727ed1f..493d306 100644
--- a/src/gallium/auxiliary/Makefile.am
+++ b/src/gallium/auxiliary/Makefile.am
@@ -39,10 +39,6 @@ indices/u_unfilled_gen.c: $(srcdir)/indices/u_unfilled_gen.py
 	$(AM_V_at)$(MKDIR_P) indices
 	$(AM_V_GEN) $(PYTHON2) $< > $@
 
-util/u_format_srgb.c: $(srcdir)/util/u_format_srgb.py
-	$(AM_V_at)$(MKDIR_P) util
-	$(AM_V_GEN) $(PYTHON2) $< > $@
-
 util/u_format_table.c: $(srcdir)/util/u_format_table.py $(srcdir)/util/u_format_pack.py $(srcdir)/util/u_format_parse.py $(srcdir)/util/u_format.csv
 	$(AM_V_at)$(MKDIR_P) util
 	$(AM_V_GEN) $(PYTHON2) $(srcdir)/util/u_format_table.py $(srcdir)/util/u_format.csv > $@
diff --git a/src/gallium/auxiliary/Makefile.sources b/src/gallium/auxiliary/Makefile.sources
index 8919783..3eae9e5 100644
--- a/src/gallium/auxiliary/Makefile.sources
+++ b/src/gallium/auxiliary/Makefile.sources
@@ -162,7 +162,6 @@ C_SOURCES := \
 GENERATED_SOURCES := \
 	indices/u_indices_gen.c \
 	indices/u_unfilled_gen.c \
-	util/u_format_srgb.c \
 	util/u_format_table.c
 
 GALLIVM_SOURCES := \
diff --git a/src/gallium/auxiliary/SConscript b/src/gallium/auxiliary/SConscript
index 31dfed3..94041d2 100644
--- a/src/gallium/auxiliary/SConscript
+++ b/src/gallium/auxiliary/SConscript
@@ -3,6 +3,7 @@ Import('*')
 from sys import executable as python_cmd
 
 env.Append(CPPPATH = [
+    '#src',
     'indices',
     'util',
 ])
@@ -22,13 +23,6 @@ env.CodeGenerate(
 )
 
 env.CodeGenerate(
-    target = 'util/u_format_srgb.c', 
-    script = 'util/u_format_srgb.py', 
-    source = [],
-    command = python_cmd + ' $SCRIPT > $TARGET'
-)
-
-env.CodeGenerate(
     target = 'util/u_format_table.c',
     script = '#src/gallium/auxiliary/util/u_format_table.py',
     source = ['#src/gallium/auxiliary/util/u_format.csv'],
diff --git a/src/gallium/auxiliary/util/u_format_pack.py b/src/gallium/auxiliary/util/u_format_pack.py
index f9496de..a553e23 100644
--- a/src/gallium/auxiliary/util/u_format_pack.py
+++ b/src/gallium/auxiliary/util/u_format_pack.py
@@ -669,7 +669,7 @@ def generate(formats):
     print '#include "u_half.h"'
     print '#include "u_format.h"'
     print '#include "u_format_other.h"'
-    print '#include "u_format_srgb.h"'
+    print '#include "util/format_srgb.h"'
     print '#include "u_format_yuv.h"'
     print '#include "u_format_zs.h"'
     print
diff --git a/src/gallium/auxiliary/util/u_format_s3tc.c b/src/gallium/auxiliary/util/u_format_s3tc.c
index 11b4602..7e05989 100644
--- a/src/gallium/auxiliary/util/u_format_s3tc.c
+++ b/src/gallium/auxiliary/util/u_format_s3tc.c
@@ -27,7 +27,7 @@
 #include "u_math.h"
 #include "u_format.h"
 #include "u_format_s3tc.h"
-#include "u_format_srgb.h"
+#include "util/format_srgb.h"
 
 
 #if defined(_WIN32) || defined(WIN32)
diff --git a/src/gallium/auxiliary/util/u_format_srgb.h b/src/gallium/auxiliary/util/u_format_srgb.h
deleted file mode 100644
index 740a919..0000000
--- a/src/gallium/auxiliary/util/u_format_srgb.h
+++ /dev/null
@@ -1,147 +0,0 @@
-/**************************************************************************
- *
- * Copyright 2010 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL
- * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
- *
- * The above copyright notice and this permission notice (including the
- * next paragraph) shall be included in all copies or substantial portions
- * of the Software.
- *
- **************************************************************************/
-
-/**
- * @file
- * SRGB translation.
- *
- * @author Brian Paul <brianp at vmware.com>
- * @author Michal Krol <michal at vmware.com>
- * @author Jose Fonseca <jfonseca at vmware.com>
- */
-
-#ifndef U_FORMAT_SRGB_H_
-#define U_FORMAT_SRGB_H_
-
-
-#include "pipe/p_compiler.h"
-#include "u_pack_color.h"
-#include "u_math.h"
-
-
-extern const float
-util_format_srgb_8unorm_to_linear_float_table[256];
-
-extern const uint8_t
-util_format_srgb_to_linear_8unorm_table[256];
-
-extern const uint8_t
-util_format_linear_to_srgb_8unorm_table[256];
-
-extern const unsigned
-util_format_linear_to_srgb_helper_table[104];
-
-
-/**
- * Convert a unclamped linear float to srgb value in the [0,255].
- */
-static INLINE uint8_t
-util_format_linear_float_to_srgb_8unorm(float x)
-{
-   /* this would be exact but (probably much) slower */
-   if (0) {
-      if (x >= 1.0f)
-         return 255;
-      else if (x >= 0.0031308f)
-         return float_to_ubyte(1.055f * powf(x, 0.41666666f) - 0.055f);
-      else if (x > 0.0f)
-         return float_to_ubyte(12.92f * x);
-      else
-         return 0;
-   }
-   else {
-      /*
-       * This is taken from https://gist.github.com/rygorous/2203834
-       * Use LUT and do linear interpolation.
-       */
-      union fi almostone, minval, f;
-      unsigned tab, bias, scale, t;
-
-      almostone.ui = 0x3f7fffff;
-      minval.ui = (127-13) << 23;
-
-      /*
-       * Clamp to [2^(-13), 1-eps]; these two values map to 0 and 1, respectively.
-       * The tests are carefully written so that NaNs map to 0, same as in the
-       * reference implementation.
-       */
-      if (!(x > minval.f))
-         x = minval.f;
-      if (x > almostone.f)
-         x = almostone.f;
-
-      /* Do the table lookup and unpack bias, scale */
-      f.f = x;
-      tab = util_format_linear_to_srgb_helper_table[(f.ui - minval.ui) >> 20];
-      bias = (tab >> 16) << 9;
-      scale = tab & 0xffff;
-
-      /* Grab next-highest mantissa bits and perform linear interpolation */
-      t = (f.ui >> 12) & 0xff;
-      return (uint8_t) ((bias + scale*t) >> 16);
-   }
-}
-
-
-/**
- * Convert an 8-bit sRGB value from non-linear space to a
- * linear RGB value in [0, 1].
- * Implemented with a 256-entry lookup table.
- */
-static INLINE float
-util_format_srgb_8unorm_to_linear_float(uint8_t x)
-{
-   return util_format_srgb_8unorm_to_linear_float_table[x];
-}
-
-
-/*
- * XXX These 2 functions probably don't make a lot of sense (but lots
- * of potential callers which most likely all don't make sense neither)
- */
-
-/**
- * Convert a 8bit normalized value from linear to srgb.
- */
-static INLINE uint8_t
-util_format_linear_to_srgb_8unorm(uint8_t x)
-{
-   return util_format_linear_to_srgb_8unorm_table[x];
-}
-
-
-/**
- * Convert a 8bit normalized value from srgb to linear.
- */
-static INLINE uint8_t
-util_format_srgb_to_linear_8unorm(uint8_t x)
-{
-   return util_format_srgb_to_linear_8unorm_table[x];
-}
-
-
-#endif /* U_FORMAT_SRGB_H_ */
diff --git a/src/gallium/auxiliary/util/u_format_srgb.py b/src/gallium/auxiliary/util/u_format_srgb.py
deleted file mode 100644
index c6c02f0..0000000
--- a/src/gallium/auxiliary/util/u_format_srgb.py
+++ /dev/null
@@ -1,155 +0,0 @@
-#!/usr/bin/env python
-
-CopyRight = '''
-/**************************************************************************
- *
- * Copyright 2010 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, sub license, 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 (including the
- * next paragraph) 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 NON-INFRINGEMENT.
- * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS 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.
- *
- **************************************************************************/
-
-/**
- * @file
- * SRGB translation.
- *
- * @author Brian Paul <brianp at vmware.com>
- * @author Michal Krol <michal at vmware.com>
- * @author Jose Fonseca <jfonseca at vmware.com>
- */
-'''
-
-
-import math
-import struct
-
-
-def srgb_to_linear(x):
-    if x <= 0.04045:
-        return x / 12.92
-    else:
-        return math.pow((x + 0.055) / 1.055, 2.4)
-
-
-def linear_to_srgb(x):
-    if x >= 0.0031308:
-        return 1.055 * math.pow(x, 0.41666666) - 0.055
-    else:
-        return 12.92 * x
-
-
-def generate_srgb_tables():
-    print 'const float'
-    print 'util_format_srgb_8unorm_to_linear_float_table[256] = {'
-    for j in range(0, 256, 4):
-        print '   ',
-        for i in range(j, j + 4):
-            print '%.7e,' % (srgb_to_linear(i / 255.0),),
-        print
-    print '};'
-    print
-    print 'const uint8_t'
-    print 'util_format_srgb_to_linear_8unorm_table[256] = {'
-    for j in range(0, 256, 16):
-        print '   ',
-        for i in range(j, j + 16):
-            print '%3u,' % (int(srgb_to_linear(i / 255.0) * 255.0 + 0.5),),
-        print
-    print '};'
-    print
-    print 'const uint8_t'
-    print 'util_format_linear_to_srgb_8unorm_table[256] = {'
-    for j in range(0, 256, 16):
-        print '   ',
-        for i in range(j, j + 16):
-            print '%3u,' % (int(linear_to_srgb(i / 255.0) * 255.0 + 0.5),),
-        print
-    print '};'
-    print
-
-# calculate the table interpolation values used in float linear to unorm8 srgb
-    numexp = 13
-    mantissa_msb = 3
-# stepshift is just used to only use every x-th float to make things faster,
-# 5 is largest value which still gives exact same table as 0
-    stepshift = 5
-    nbuckets = numexp << mantissa_msb
-    bucketsize = (1 << (23 - mantissa_msb)) >> stepshift
-    mantshift = 12
-    valtable = []
-    sum_aa = float(bucketsize)
-    sum_ab = 0.0
-    sum_bb = 0.0
-    for i in range(0, bucketsize):
-        j = (i << stepshift) >> mantshift
-        sum_ab += j
-        sum_bb += j*j
-    inv_det = 1.0 / (sum_aa * sum_bb - sum_ab * sum_ab)
-
-    for bucket in range(0, nbuckets):
-        start = ((127 - numexp) << 23) + bucket*(bucketsize << stepshift)
-        sum_a = 0.0
-        sum_b = 0.0
- 
-        for i in range(0, bucketsize):
-            j = (i << stepshift) >> mantshift
-            fint = start + (i << stepshift)
-            ffloat = struct.unpack('f', struct.pack('I', fint))[0]
-            val = linear_to_srgb(ffloat) * 255.0 + 0.5
-            sum_a += val
-            sum_b += j*val
-
-        solved_a = inv_det * (sum_bb*sum_a - sum_ab*sum_b)
-        solved_b = inv_det * (sum_aa*sum_b - sum_ab*sum_a)
-
-        scaled_a = solved_a * 65536.0 / 512.0
-        scaled_b = solved_b * 65536.0
- 
-        int_a = int(scaled_a + 0.5)
-        int_b = int(scaled_b + 0.5)
-
-        valtable.append((int_a << 16) + int_b)
-
-    print 'const unsigned'
-    print 'util_format_linear_to_srgb_helper_table[104] = {'
-
-    for j in range(0, nbuckets, 4):
-        print '   ',
-        for i in range(j, j + 4):
-            print '0x%08x,' % (valtable[i],),
-        print
-    print '};'
-    print
-
-def main():
-    print '/* This file is autogenerated by u_format_srgb.py. Do not edit directly. */'
-    print
-    # This will print the copyright message on the top of this file
-    print CopyRight.strip()
-    print
-    print '#include "u_format_srgb.h"'
-    print
-    generate_srgb_tables()    
-
-
-if __name__ == '__main__':
-    main()
diff --git a/src/gallium/drivers/llvmpipe/SConscript b/src/gallium/drivers/llvmpipe/SConscript
index 20500fd..1bea611 100644
--- a/src/gallium/drivers/llvmpipe/SConscript
+++ b/src/gallium/drivers/llvmpipe/SConscript
@@ -20,7 +20,7 @@ env.Alias('llvmpipe', llvmpipe)
 if not env['embedded']:
     env = env.Clone()
 
-    env.Prepend(LIBS = [llvmpipe] + gallium)
+    env.Prepend(LIBS = [llvmpipe, gallium, mesautil])
 
     tests = [
         'format',
diff --git a/src/gallium/drivers/nouveau/Makefile.am b/src/gallium/drivers/nouveau/Makefile.am
index ef48380..82741d2 100644
--- a/src/gallium/drivers/nouveau/Makefile.am
+++ b/src/gallium/drivers/nouveau/Makefile.am
@@ -49,4 +49,5 @@ nouveau_compiler_SOURCES = \
 nouveau_compiler_LDADD = \
 	libnouveau.la \
 	../../auxiliary/libgallium.la \
+	$(top_builddir)/src/util/libmesautil.la \
 	$(GALLIUM_COMMON_LIB_DEPS)
diff --git a/src/gallium/drivers/nouveau/nv50/nv50_state.c b/src/gallium/drivers/nouveau/nv50/nv50_state.c
index 915ee26..48bc079 100644
--- a/src/gallium/drivers/nouveau/nv50/nv50_state.c
+++ b/src/gallium/drivers/nouveau/nv50/nv50_state.c
@@ -24,7 +24,7 @@
 #include "util/u_helpers.h"
 #include "util/u_inlines.h"
 #include "util/u_transfer.h"
-#include "util/u_format_srgb.h"
+#include "util/format_srgb.h"
 
 #include "tgsi/tgsi_parse.h"
 
diff --git a/src/gallium/targets/graw-gdi/SConscript b/src/gallium/targets/graw-gdi/SConscript
index 352efe9..dc7b7f1 100644
--- a/src/gallium/targets/graw-gdi/SConscript
+++ b/src/gallium/targets/graw-gdi/SConscript
@@ -10,6 +10,7 @@ env.Append(CPPPATH = [
 ])
 
 env.Prepend(LIBS = [
+    mesautils,
     gallium,
     'gdi32',
     'user32',
diff --git a/src/gallium/targets/graw-null/SConscript b/src/gallium/targets/graw-null/SConscript
index ebac172..20c8b7d 100644
--- a/src/gallium/targets/graw-null/SConscript
+++ b/src/gallium/targets/graw-null/SConscript
@@ -16,7 +16,7 @@ sources = [
     graw_util,
 ]
 
-env.Prepend(LIBS = [gallium])
+env.Prepend(LIBS = [mesautil, gallium])
 
 # TODO: write a wrapper function http://www.scons.org/wiki/WrapperFunctions
 graw = env.SharedLibrary(
diff --git a/src/gallium/targets/graw-xlib/SConscript b/src/gallium/targets/graw-xlib/SConscript
index 76e4d4f..886811b 100644
--- a/src/gallium/targets/graw-xlib/SConscript
+++ b/src/gallium/targets/graw-xlib/SConscript
@@ -7,6 +7,7 @@ env = env.Clone()
 
 env.Prepend(LIBS = [
     ws_xlib,
+    mesautil,
     gallium,
 ])
 
diff --git a/src/gallium/targets/pipe-loader/Makefile.am b/src/gallium/targets/pipe-loader/Makefile.am
index a4e0407..ee93078 100644
--- a/src/gallium/targets/pipe-loader/Makefile.am
+++ b/src/gallium/targets/pipe-loader/Makefile.am
@@ -38,6 +38,7 @@ pipe_LTLIBRARIES =
 
 PIPE_LIBS = \
 	$(top_builddir)/src/gallium/auxiliary/libgallium.la \
+        $(top_builddir)/src/util/libmesautil.la \
 	$(top_builddir)/src/gallium/drivers/rbug/librbug.la \
 	$(top_builddir)/src/gallium/drivers/trace/libtrace.la \
 	$(top_builddir)/src/gallium/drivers/galahad/libgalahad.la \
@@ -96,7 +97,6 @@ nodist_EXTRA_pipe_r300_la_SOURCES = dummy.cpp
 pipe_r300_la_LIBADD = \
 	$(PIPE_LIBS) \
 	$(top_builddir)/src/gallium/winsys/radeon/drm/libradeonwinsys.la \
-        $(top_builddir)/src/util/libmesautil.la \
 	$(top_builddir)/src/gallium/drivers/r300/libr300-helper.la \
 	$(top_builddir)/src/gallium/drivers/r300/libr300.la \
 	$(LIBDRM_LIBS) \
diff --git a/src/gallium/tests/graw/SConscript b/src/gallium/tests/graw/SConscript
index 8723807..c5fa3fe 100644
--- a/src/gallium/tests/graw/SConscript
+++ b/src/gallium/tests/graw/SConscript
@@ -2,7 +2,7 @@ Import('*')
 
 env = env.Clone()
 
-env.Prepend(LIBS = [gallium])
+env.Prepend(LIBS = [mesautil, gallium])
 
 env.Prepend(LIBPATH = [graw.dir])
 env.Prepend(LIBS = ['graw'])
diff --git a/src/gallium/tests/unit/SConscript b/src/gallium/tests/unit/SConscript
index edc1e80..a816e2f 100644
--- a/src/gallium/tests/unit/SConscript
+++ b/src/gallium/tests/unit/SConscript
@@ -2,7 +2,7 @@ Import('*')
 
 env = env.Clone()
 
-env.Prepend(LIBS = [gallium])
+env.Prepend(LIBS = [mesautil, gallium])
 
 if env['platform'] in ('freebsd8', 'sunos'):
     env.Append(LIBS = ['m'])
diff --git a/src/util/Makefile.am b/src/util/Makefile.am
index a2aeafc..e738ab0 100644
--- a/src/util/Makefile.am
+++ b/src/util/Makefile.am
@@ -23,6 +23,10 @@ SUBDIRS = . tests
 
 include Makefile.sources
 
+BUILT_SOURCES = $(MESA_UTIL_GENERATED_FILES)
+
+CLEANFILES = $(BUILT_SOURCES)
+
 noinst_LTLIBRARIES = libmesautil.la
 
 libmesautil_la_CPPFLAGS = \
@@ -30,7 +34,12 @@ libmesautil_la_CPPFLAGS = \
 	-I$(top_srcdir)/include \
 	$(VISIBILITY_CFLAGS)
 
-libmesautil_la_SOURCES = $(MESA_UTIL_FILES)
+libmesautil_la_SOURCES = \
+	$(MESA_UTIL_FILES) \
+        $(MESA_UTIL_GENERATED_FILES)
+
+format_srgb.c: $(srcdir)/format_srgb.py
+	$(AM_V_GEN) $(PYTHON2) $< > $@
 
 ### Tests:
 
diff --git a/src/util/Makefile.sources b/src/util/Makefile.sources
index 5daa731..b99aa25 100644
--- a/src/util/Makefile.sources
+++ b/src/util/Makefile.sources
@@ -1,3 +1,6 @@
 MESA_UTIL_FILES :=	\
 	hash_table.c	\
 	ralloc.c
+
+MESA_UTIL_GENERATED_FILES = \
+	format_srgb.c
diff --git a/src/util/SConscript b/src/util/SConscript
index 8afeeda..84803c0 100644
--- a/src/util/SConscript
+++ b/src/util/SConscript
@@ -11,10 +11,20 @@ env.Prepend(CPPPATH = [
     '#src/util',
 ])
 
+env.CodeGenerate(
+    target = 'format_srgb.c',
+    script = 'format_srgb.py',
+    source = [],
+    command = python_cmd + ' $SCRIPT > $TARGET'
+)
+
 # parse Makefile.sources
 source_lists = env.ParseSourceList('Makefile.sources')
 
-mesautil_sources = source_lists['MESA_UTIL_FILES']
+mesautil_sources = (
+    source_lists['MESA_UTIL_FILES'] +
+    source_lists['MESA_UTIL_GENERATED_FILES']
+)
 
 mesautil = env.ConvenienceLibrary(
     target = 'mesautil',
diff --git a/src/util/format_srgb.h b/src/util/format_srgb.h
new file mode 100644
index 0000000..8e92c38
--- /dev/null
+++ b/src/util/format_srgb.h
@@ -0,0 +1,133 @@
+/**************************************************************************
+ *
+ * Copyright 2010 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, sub license, 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 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 NON-INFRINGEMENT. IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS 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.
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ **************************************************************************/
+
+/**
+ * @file
+ * SRGB translation.
+ *
+ * @author Brian Paul <brianp at vmware.com>
+ * @author Michal Krol <michal at vmware.com>
+ * @author Jose Fonseca <jfonseca at vmware.com>
+ */
+
+#ifndef U_FORMAT_SRGB_H_
+#define U_FORMAT_SRGB_H_
+
+#include <stdint.h>
+
+extern const float
+util_format_srgb_8unorm_to_linear_float_table[256];
+
+extern const uint8_t
+util_format_srgb_to_linear_8unorm_table[256];
+
+extern const uint8_t
+util_format_linear_to_srgb_8unorm_table[256];
+
+extern const unsigned
+util_format_linear_to_srgb_helper_table[104];
+
+
+/**
+ * Convert a unclamped linear float to srgb value in the [0,255].
+ */
+static inline uint8_t
+util_format_linear_float_to_srgb_8unorm(float x)
+{
+   /*
+    * This is taken from https://gist.github.com/rygorous/2203834
+    * Use LUT and do linear interpolation.
+    */
+   union {
+      uint32_t ui;
+      float f;
+   } almostone, minval, f;
+   unsigned tab, bias, scale, t;
+
+   almostone.ui = 0x3f7fffff;
+   minval.ui = (127-13) << 23;
+
+   /*
+    * Clamp to [2^(-13), 1-eps]; these two values map to 0 and 1, respectively.
+    * The tests are carefully written so that NaNs map to 0, same as in the
+    * reference implementation.
+    */
+   if (!(x > minval.f))
+      x = minval.f;
+   if (x > almostone.f)
+      x = almostone.f;
+
+   /* Do the table lookup and unpack bias, scale */
+   f.f = x;
+   tab = util_format_linear_to_srgb_helper_table[(f.ui - minval.ui) >> 20];
+   bias = (tab >> 16) << 9;
+   scale = tab & 0xffff;
+
+   /* Grab next-highest mantissa bits and perform linear interpolation */
+   t = (f.ui >> 12) & 0xff;
+   return (uint8_t) ((bias + scale*t) >> 16);
+}
+
+
+/**
+ * Convert an 8-bit sRGB value from non-linear space to a
+ * linear RGB value in [0, 1].
+ * Implemented with a 256-entry lookup table.
+ */
+static inline float
+util_format_srgb_8unorm_to_linear_float(uint8_t x)
+{
+   return util_format_srgb_8unorm_to_linear_float_table[x];
+}
+
+
+/*
+ * XXX These 2 functions probably don't make a lot of sense (but lots
+ * of potential callers which most likely all don't make sense neither)
+ */
+
+/**
+ * Convert a 8bit normalized value from linear to srgb.
+ */
+static inline uint8_t
+util_format_linear_to_srgb_8unorm(uint8_t x)
+{
+   return util_format_linear_to_srgb_8unorm_table[x];
+}
+
+
+/**
+ * Convert a 8bit normalized value from srgb to linear.
+ */
+static inline uint8_t
+util_format_srgb_to_linear_8unorm(uint8_t x)
+{
+   return util_format_srgb_to_linear_8unorm_table[x];
+}
+
+
+#endif /* U_FORMAT_SRGB_H_ */
diff --git a/src/util/format_srgb.py b/src/util/format_srgb.py
new file mode 100644
index 0000000..d5cbcf7
--- /dev/null
+++ b/src/util/format_srgb.py
@@ -0,0 +1,155 @@
+#!/usr/bin/env python
+
+CopyRight = '''
+/**************************************************************************
+ *
+ * Copyright 2010 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, sub license, 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 (including the
+ * next paragraph) 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 NON-INFRINGEMENT.
+ * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS 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.
+ *
+ **************************************************************************/
+
+/**
+ * @file
+ * SRGB translation.
+ *
+ * @author Brian Paul <brianp at vmware.com>
+ * @author Michal Krol <michal at vmware.com>
+ * @author Jose Fonseca <jfonseca at vmware.com>
+ */
+'''
+
+
+import math
+import struct
+
+
+def srgb_to_linear(x):
+    if x <= 0.04045:
+        return x / 12.92
+    else:
+        return math.pow((x + 0.055) / 1.055, 2.4)
+
+
+def linear_to_srgb(x):
+    if x >= 0.0031308:
+        return 1.055 * math.pow(x, 0.41666666) - 0.055
+    else:
+        return 12.92 * x
+
+
+def generate_srgb_tables():
+    print 'const float'
+    print 'util_format_srgb_8unorm_to_linear_float_table[256] = {'
+    for j in range(0, 256, 4):
+        print '   ',
+        for i in range(j, j + 4):
+            print '%.7e,' % (srgb_to_linear(i / 255.0),),
+        print
+    print '};'
+    print
+    print 'const uint8_t'
+    print 'util_format_srgb_to_linear_8unorm_table[256] = {'
+    for j in range(0, 256, 16):
+        print '   ',
+        for i in range(j, j + 16):
+            print '%3u,' % (int(srgb_to_linear(i / 255.0) * 255.0 + 0.5),),
+        print
+    print '};'
+    print
+    print 'const uint8_t'
+    print 'util_format_linear_to_srgb_8unorm_table[256] = {'
+    for j in range(0, 256, 16):
+        print '   ',
+        for i in range(j, j + 16):
+            print '%3u,' % (int(linear_to_srgb(i / 255.0) * 255.0 + 0.5),),
+        print
+    print '};'
+    print
+
+# calculate the table interpolation values used in float linear to unorm8 srgb
+    numexp = 13
+    mantissa_msb = 3
+# stepshift is just used to only use every x-th float to make things faster,
+# 5 is largest value which still gives exact same table as 0
+    stepshift = 5
+    nbuckets = numexp << mantissa_msb
+    bucketsize = (1 << (23 - mantissa_msb)) >> stepshift
+    mantshift = 12
+    valtable = []
+    sum_aa = float(bucketsize)
+    sum_ab = 0.0
+    sum_bb = 0.0
+    for i in range(0, bucketsize):
+        j = (i << stepshift) >> mantshift
+        sum_ab += j
+        sum_bb += j*j
+    inv_det = 1.0 / (sum_aa * sum_bb - sum_ab * sum_ab)
+
+    for bucket in range(0, nbuckets):
+        start = ((127 - numexp) << 23) + bucket*(bucketsize << stepshift)
+        sum_a = 0.0
+        sum_b = 0.0
+
+        for i in range(0, bucketsize):
+            j = (i << stepshift) >> mantshift
+            fint = start + (i << stepshift)
+            ffloat = struct.unpack('f', struct.pack('I', fint))[0]
+            val = linear_to_srgb(ffloat) * 255.0 + 0.5
+            sum_a += val
+            sum_b += j*val
+
+        solved_a = inv_det * (sum_bb*sum_a - sum_ab*sum_b)
+        solved_b = inv_det * (sum_aa*sum_b - sum_ab*sum_a)
+
+        scaled_a = solved_a * 65536.0 / 512.0
+        scaled_b = solved_b * 65536.0
+
+        int_a = int(scaled_a + 0.5)
+        int_b = int(scaled_b + 0.5)
+
+        valtable.append((int_a << 16) + int_b)
+
+    print 'const unsigned'
+    print 'util_format_linear_to_srgb_helper_table[104] = {'
+
+    for j in range(0, nbuckets, 4):
+        print '   ',
+        for i in range(j, j + 4):
+            print '0x%08x,' % (valtable[i],),
+        print
+    print '};'
+    print
+
+def main():
+    print '/* This file is autogenerated by u_format_srgb.py. Do not edit directly. */'
+    print
+    # This will print the copyright message on the top of this file
+    print CopyRight.strip()
+    print
+    print '#include "format_srgb.h"'
+    print
+    generate_srgb_tables()
+
+
+if __name__ == '__main__':
+    main()
-- 
2.0.1



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