add the SiS driver - no kernel driver yet

(build tested, but not physically tested)

1 files changed, 181 insertions, 0 deletions

diff --git a/src/mesa/drivers/dri/sis/sis_fog.c b/src/mesa/drivers/dri/sis/sis_fog.c
new file mode 100644
index 00000000000..8daa9a0f5e3
--- /dev/null
+++ b/src/mesa/drivers/dri/sis/sis_fog.c
@@ -0,0 +1,181 @@
+/**************************************************************************
+
+Copyright 2000 Silicon Integrated Systems Corp, Inc., HsinChu, Taiwan.
+Copyright 2003 Eric Anholt
+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
+on 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
+ATI, PRECISION INSIGHT AND/OR THEIR 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.
+
+**************************************************************************/
+/* $XFree86: xc/lib/GL/mesa/src/drv/sis/sis_fog.c,v 1.3 2000/09/26 15:56:48 tsi Exp $ */
+
+/*
+ * Authors:
+ *   Sung-Ching Lin <[email protected]>
+ *   Eric Anholt <[email protected]>
+ */
+
+#include "sis_context.h"
+#include "sis_state.h"
+#include "swrast/swrast.h"
+#include "macros.h"
+
+static GLint convertFtToFogFt( GLfloat dwInValue );
+
+void
+sisDDFogfv( GLcontext *ctx, GLenum pname, const GLfloat *params )
+{
+   sisContextPtr smesa = SIS_CONTEXT(ctx);
+   __GLSiSHardware *current = &smesa->current;
+
+   float fArg;
+   GLint fogColor;
+
+   switch (pname)
+   {
+   case GL_FOG_MODE:
+      current->hwFog &= ~MASK_FogMode;
+      switch (ctx->Fog.Mode)
+      {
+      case GL_LINEAR:
+         current->hwFog |= FOGMODE_LINEAR;
+         _swrast_allow_pixel_fog( ctx, GL_TRUE );
+         _swrast_allow_vertex_fog( ctx, GL_FALSE );
+         break;
+      case GL_EXP:
+         if (ctx->Hint.Fog == GL_NICEST || smesa->AGPCmdModeEnabled) {
+            current->hwFog |= FOGMODE_EXP;
+            _swrast_allow_pixel_fog( ctx, GL_TRUE );
+            _swrast_allow_vertex_fog( ctx, GL_FALSE );
+         } else { /* GL_DONTCARE or GL_FASTEST */
+            current->hwFog |= FOGMODE_CHEAP;
+            _swrast_allow_pixel_fog( ctx, GL_FALSE );
+            _swrast_allow_vertex_fog( ctx, GL_TRUE );
+         }
+         break;
+      case GL_EXP2:
+         current->hwFog |= FOGMODE_EXP2;
+         _swrast_allow_pixel_fog( ctx, GL_TRUE );
+         _swrast_allow_vertex_fog( ctx, GL_FALSE );
+         break;
+      }
+      break;
+   case GL_FOG_DENSITY:
+      current->hwFogDensity = convertFtToFogFt( ctx->Fog.Density );
+      break;
+   case GL_FOG_START:
+   case GL_FOG_END:
+      fArg = 1.0 / (ctx->Fog.End - ctx->Fog.Start);
+      current->hwFogInverse = doFPtoFixedNoRound( fArg, 10 );
+      if (pname == GL_FOG_END)
+      {
+         if (smesa->Chipset == PCI_CHIP_SIS300)
+            current->hwFogFar = doFPtoFixedNoRound( ctx->Fog.End, 10 );
+         else
+            current->hwFogFar = doFPtoFixedNoRound( ctx->Fog.End, 6 );
+      }
+      break;
+   case GL_FOG_INDEX:
+      /* TODO */
+      break;
+   case GL_FOG_COLOR:
+      fogColor  = FLOAT_TO_UBYTE( ctx->Fog.Color[0] ) << 16;
+      fogColor |= FLOAT_TO_UBYTE( ctx->Fog.Color[1] ) << 8;
+      fogColor |= FLOAT_TO_UBYTE( ctx->Fog.Color[2] );
+      current->hwFog &= 0xff000000;
+      current->hwFog |= fogColor;
+      break;
+   }
+}
+
+GLint
+doFPtoFixedNoRound( GLfloat dwInValue, int nFraction )
+{
+   GLint dwMantissa;
+   int nTemp;
+   union { int i; float f; } u;
+   GLint val;
+
+   u.f = dwInValue;
+   val = u.i;
+
+   if (val == 0)
+      return 0;
+   nTemp = (int) (val & 0x7F800000) >> 23;
+   nTemp = nTemp - 127 + nFraction - 23;
+   dwMantissa = (val & 0x007FFFFF) | 0x00800000;
+
+   if (nTemp < -25)
+       return 0;
+   if (nTemp > 0)
+      dwMantissa <<= nTemp;
+   else {
+      nTemp = -nTemp;
+      dwMantissa >>= nTemp;
+   }
+   if (val & 0x80000000)
+      dwMantissa = ~dwMantissa + 1;
+   return dwMantissa;
+}
+
+/* s[8].23->s[7].10 */
+static GLint
+convertFtToFogFt( GLfloat dwInValue )
+{
+   GLint dwMantissa, dwExp;
+   GLint dwRet;
+   union { int i; float f; } u;
+   GLint val;
+
+   u.f = dwInValue;
+   val = u.i;
+
+   if (val == 0)
+      return 0;
+
+   /* ----- Standard float Format: s[8].23                          -----
+    * -----     = (-1)^S * 2^(E      - 127) * (1 + M        / 2^23) -----
+    * -----     = (-1)^S * 2^((E-63) -  64) * (1 + (M/2^13) / 2^10) -----
+    * ----- Density float Format:  s[7].10                          -----
+    * -----     New Exponential = E - 63                            -----
+    * -----     New Mantissa    = M / 2^13                          -----
+    * -----                                                         -----
+    */
+
+   dwExp = (val & 0x7F800000) >> 23;
+   dwExp -= 63;
+
+   if (dwExp < 0)
+      return 0;
+
+   if (dwExp <= 0x7F)
+      dwMantissa = (val & 0x007FFFFF) >> (23 - 10);
+   else {
+      /* ----- To Return +Max(or -Max) ----- */
+      dwExp = 0x7F;
+      dwMantissa = 0x3FF;
+   }
+
+   dwRet = (val & 0x80000000) >> (31 - 17);  /* Shift Sign Bit */
+
+   dwRet |= (dwExp << 10) | dwMantissa;
+
+   return dwRet;
+}