mesa: implement clamping controls (ARB_color_buffer_float)

Squashed commit of the following:

Author: Marek Olšák <maraeo@gmail.com>

    mesa: fix getteximage so that it doesn't clamp values
    mesa: update the compute_version function
    mesa: add display list support for ARB_color_buffer_float
    mesa: fix glGet query with GL_ALPHA_TEST_REF and ARB_color_buffer_float

commit b2f6ddf907935b2594d2831ddab38cf57a1729ce
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Tue Aug 31 16:50:57 2010 +0200

    mesa: document known possible deviations from ARB_color_buffer_float

commit 5458935be800c1b19d1c9d1569dc4fa30a97e8b8
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Tue Aug 24 21:54:56 2010 +0200

    mesa: expose GL_ARB_color_buffer_float

commit aef5c3c6be6edd076e955e37c80905bc447f8a82
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Thu Aug 26 18:12:34 2010 +0200

    mesa, mesa/st: handle read color clamping properly

    (I'll squash the st/mesa part to a separate commit. -Marek)

    We set IMAGE_CLAMP_BIT in the caller based on _ClampReadColor, where
    the operation mandates it.

    TODO: did I get the set of operations mandating it right?

commit 3a9cb5e59b676b6148c50907ce6eef5441677e36
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Thu Aug 26 18:09:41 2010 +0200

    mesa: respect color clamping in texenv programs (v2)

    Changes in v2:
    - Fix attributes other than vertex color sometimes getting clamped

commit de26f9e47e886e176aab6e5a2c3d4481efb64362
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Thu Aug 26 18:05:53 2010 +0200

    mesa: restore color clamps on glPopAttrib

commit a55ac3c300c189616627c05d924c40a8b55bfafa
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Thu Aug 26 18:04:26 2010 +0200

    mesa: clamp color queries if and only if fragment clamping is enabled

commit 9940a3e31c2fb76cc3d28b15ea78dde369825107
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Wed Aug 25 00:00:16 2010 +0200

    mesa: introduce derived _ClampXxxColor state resolving FIXED_ONLY

    To do this, we make ClampColor call FLUSH_VERTICES with the appropriate
    _NEW flag.

    We introduce _NEW_FRAG_CLAMP since fragment clamping has wide-ranging
    effects, despite being in the Color attrib group.

    This may be easily changed by s/_NEW_FRAG_CLAMP/_NEW_COLOR/g

commit 6244c446e3beed5473b4e811d10787e4019f59d6
Author: Luca Barbieri <luca@luca-barbieri.com>
Date:   Thu Aug 26 17:58:24 2010 +0200

    mesa: add unclamped color parameters

1 files changed, 41 insertions, 4 deletions

diff --git a/src/mesa/main/get.c b/src/mesa/main/get.c
index 81a2a4e..9090ca6 100644
--- a/src/mesa/main/get.c
+++ b/src/mesa/main/get.c
@@ -131,6 +131,7 @@ enum value_extra {
    EXTRA_VERSION_32,
    EXTRA_VERSION_ES2,
    EXTRA_NEW_BUFFERS, 
+   EXTRA_NEW_FRAG_CLAMP,
    EXTRA_VALID_DRAW_BUFFER,
    EXTRA_VALID_TEXTURE_UNIT,
    EXTRA_FLUSH_CURRENT,
@@ -223,6 +224,11 @@ static const int extra_new_buffers[] = {
    EXTRA_END
 };
 
+static const int extra_new_frag_clamp[] = {
+   EXTRA_NEW_FRAG_CLAMP,
+   EXTRA_END
+};
+
 static const int extra_valid_draw_buffer[] = {
    EXTRA_VALID_DRAW_BUFFER,
    EXTRA_END
@@ -374,7 +380,7 @@ static const struct value_desc values[] = {
    { GL_BLEND, CONTEXT_BIT0(Color.BlendEnabled), NO_EXTRA },
    { GL_BLEND_SRC, CONTEXT_ENUM(Color.Blend[0].SrcRGB), NO_EXTRA },
    { GL_BLUE_BITS, BUFFER_INT(Visual.blueBits), extra_new_buffers },
-   { GL_COLOR_CLEAR_VALUE, CONTEXT_FIELD(Color.ClearColor[0], TYPE_FLOATN_4), NO_EXTRA },
+   { GL_COLOR_CLEAR_VALUE, LOC_CUSTOM, TYPE_FLOATN_4, 0, extra_new_frag_clamp },
    { GL_COLOR_WRITEMASK, LOC_CUSTOM, TYPE_INT_4, 0, NO_EXTRA },
    { GL_CULL_FACE, CONTEXT_BOOL(Polygon.CullFlag), NO_EXTRA },
    { GL_CULL_FACE_MODE, CONTEXT_ENUM(Polygon.CullFaceMode), NO_EXTRA },
@@ -511,7 +517,7 @@ static const struct value_desc values[] = {
    { GL_LIGHT_MODEL_TWO_SIDE, CONTEXT_BOOL(Light.Model.TwoSide), NO_EXTRA },
    { GL_ALPHA_TEST, CONTEXT_BOOL(Color.AlphaEnabled), NO_EXTRA },
    { GL_ALPHA_TEST_FUNC, CONTEXT_ENUM(Color.AlphaFunc), NO_EXTRA },
-   { GL_ALPHA_TEST_REF, CONTEXT_FIELD(Color.AlphaRef, TYPE_FLOATN), NO_EXTRA },
+   { GL_ALPHA_TEST_REF, LOC_CUSTOM, TYPE_FLOATN, 0, extra_new_frag_clamp },
    { GL_BLEND_DST, CONTEXT_ENUM(Color.Blend[0].DstRGB), NO_EXTRA },
    { GL_CLIP_PLANE0, CONTEXT_BIT0(Transform.ClipPlanesEnabled), NO_EXTRA },
    { GL_CLIP_PLANE1, CONTEXT_BIT1(Transform.ClipPlanesEnabled), NO_EXTRA },
@@ -530,7 +536,7 @@ static const struct value_desc values[] = {
      extra_flush_current_valid_texture_unit },
    { GL_DISTANCE_ATTENUATION_EXT, CONTEXT_FLOAT3(Point.Params[0]), NO_EXTRA },
    { GL_FOG, CONTEXT_BOOL(Fog.Enabled), NO_EXTRA },
-   { GL_FOG_COLOR, CONTEXT_FIELD(Fog.Color[0], TYPE_FLOATN_4), NO_EXTRA },
+   { GL_FOG_COLOR, LOC_CUSTOM, TYPE_FLOATN_4, 0, extra_new_frag_clamp },
    { GL_FOG_DENSITY, CONTEXT_FLOAT(Fog.Density), NO_EXTRA },
    { GL_FOG_END, CONTEXT_FLOAT(Fog.End), NO_EXTRA },
    { GL_FOG_HINT, CONTEXT_ENUM(Hint.Fog), NO_EXTRA },
@@ -674,7 +680,7 @@ static const struct value_desc values[] = {
    /* GL_ARB_draw_buffers */
    { GL_MAX_DRAW_BUFFERS_ARB, CONTEXT_INT(Const.MaxDrawBuffers), NO_EXTRA },
 
-   { GL_BLEND_COLOR_EXT, CONTEXT_FIELD(Color.BlendColor[0], TYPE_FLOATN_4), NO_EXTRA },
+   { GL_BLEND_COLOR_EXT, LOC_CUSTOM, TYPE_FLOATN_4, 0, extra_new_frag_clamp },
    /* GL_ARB_fragment_program */
    { GL_MAX_TEXTURE_IMAGE_UNITS_ARB, /* == GL_MAX_TEXTURE_IMAGE_UNITS_NV */
      CONTEXT_INT(Const.MaxTextureImageUnits),
@@ -1219,6 +1225,9 @@ static const struct value_desc values[] = {
      CONTEXT_INT(Const.MaxVertexVaryingComponents),
      extra_ARB_geometry_shader4 },
 
+   /* GL_ARB_color_buffer_float */
+   { GL_RGBA_FLOAT_MODE_ARB, BUFFER_FIELD(Visual.floatMode, TYPE_BOOLEAN), 0 },
+
    /* GL_EXT_gpu_shader4 / GL 3.0 */
    { GL_MIN_PROGRAM_TEXEL_OFFSET,
      CONTEXT_INT(Const.MinProgramTexelOffset),
@@ -1633,6 +1642,30 @@ find_custom_value(struct gl_context *ctx, const struct value_desc *d, union valu
       v->value_int = ctx->Array.ArrayObj->PointSize.BufferObj->Name;
       break;
 
+   case GL_FOG_COLOR:
+      if(ctx->Color._ClampFragmentColor)
+         COPY_4FV(v->value_float_4, ctx->Fog.Color);
+      else
+         COPY_4FV(v->value_float_4, ctx->Fog.ColorUnclamped);
+      break;
+   case GL_COLOR_CLEAR_VALUE:
+      if(ctx->Color._ClampFragmentColor)
+         COPY_4FV(v->value_float_4, ctx->Color.ClearColor);
+      else
+         COPY_4FV(v->value_float_4, ctx->Color.ClearColorUnclamped);
+      break;
+   case GL_BLEND_COLOR_EXT:
+      if(ctx->Color._ClampFragmentColor)
+         COPY_4FV(v->value_float_4, ctx->Color.BlendColor);
+      else
+         COPY_4FV(v->value_float_4, ctx->Color.BlendColorUnclamped);
+      break;
+   case GL_ALPHA_TEST_REF:
+      if(ctx->Color._ClampFragmentColor)
+         v->value_float = ctx->Color.AlphaRef;
+      else
+         v->value_float = ctx->Color.AlphaRefUnclamped;
+      break;
    case GL_MAX_VERTEX_UNIFORM_VECTORS:
       v->value_int = ctx->Const.VertexProgram.MaxUniformComponents / 4;
       break;
@@ -1687,6 +1720,10 @@ check_extra(struct gl_context *ctx, const char *func, const struct value_desc *d
 	    enabled++;
 	 }
 	 break;
+      case EXTRA_NEW_FRAG_CLAMP:
+         if (ctx->NewState & (_NEW_BUFFERS | _NEW_FRAG_CLAMP))
+            _mesa_update_state(ctx);
+         break;
       case EXTRA_VERSION_ES2:
 	 if (ctx->API == API_OPENGLES2) {
 	    total++;