mesa: Add support for ARB_depth_clamp.

This currently doesn't include fixing up the cliptests in the assembly
paths to support ARB_depth_clamp, so enabling depth_clamp forces the C path.

5 files changed, 35 insertions, 0 deletions

diff --git a/src/mesa/main/attrib.c b/src/mesa/main/attrib.c
index ab99ca1c64..0fb8fa3bba 100644
--- a/src/mesa/main/attrib.c
+++ b/src/mesa/main/attrib.c
@@ -74,6 +74,7 @@ struct gl_enable_attrib
    GLboolean Convolution2D;
    GLboolean Separable2D;
    GLboolean CullFace;
+   GLboolean DepthClamp;
    GLboolean DepthTest;
    GLboolean Dither;
    GLboolean Fog;
@@ -265,6 +266,7 @@ _mesa_PushAttrib(GLbitfield mask)
       attr->Convolution2D = ctx->Pixel.Convolution2DEnabled;
       attr->Separable2D = ctx->Pixel.Separable2DEnabled;
       attr->CullFace = ctx->Polygon.CullFlag;
+      attr->DepthClamp = ctx->Transform.DepthClamp;
       attr->DepthTest = ctx->Depth.Test;
       attr->Dither = ctx->Color.DitherFlag;
       attr->Fog = ctx->Fog.Enabled;
@@ -514,6 +516,8 @@ pop_enable_group(GLcontext *ctx, const struct gl_enable_attrib *enable)
                    enable->ColorTable[COLORTABLE_POSTCOLORMATRIX],
                    GL_POST_COLOR_MATRIX_COLOR_TABLE);
    TEST_AND_UPDATE(ctx->Polygon.CullFlag, enable->CullFace, GL_CULL_FACE);
+   TEST_AND_UPDATE(ctx->Transform.DepthClamp, enable->DepthClamp,
+		   GL_DEPTH_CLAMP);
    TEST_AND_UPDATE(ctx->Depth.Test, enable->DepthTest, GL_DEPTH_TEST);
    TEST_AND_UPDATE(ctx->Color.DitherFlag, enable->Dither, GL_DITHER);
    TEST_AND_UPDATE(ctx->Pixel.Convolution1DEnabled, enable->Convolution1D,
@@ -1221,6 +1225,9 @@ _mesa_PopAttrib(void)
                if (xform->RescaleNormals != ctx->Transform.RescaleNormals)
                   _mesa_set_enable(ctx, GL_RESCALE_NORMAL_EXT,
                                    ctx->Transform.RescaleNormals);
+               if (xform->DepthClamp != ctx->Transform.DepthClamp)
+                  _mesa_set_enable(ctx, GL_DEPTH_CLAMP,
+                                   ctx->Transform.DepthClamp);
             }
             break;
          case GL_TEXTURE_BIT:
diff --git a/src/mesa/main/enable.c b/src/mesa/main/enable.c
index 4bc54771e9..d066153fc2 100644
--- a/src/mesa/main/enable.c
+++ b/src/mesa/main/enable.c
@@ -37,6 +37,7 @@
 #include "mtypes.h"
 #include "enums.h"
 #include "math/m_matrix.h"
+#include "math/m_xform.h"
 #include "api_arrayelt.h"
 
 
@@ -947,6 +948,20 @@ _mesa_set_enable(GLcontext *ctx, GLenum cap, GLboolean state)
          ctx->Depth.BoundsTest = state;
          break;
 
+      case GL_DEPTH_CLAMP:
+         if (ctx->Transform.DepthClamp == state)
+            return;
+	 /* Neither the x86 nor sparc asm cliptest functions have been updated
+	  * for ARB_depth_clamp, so force the C paths.
+	  */
+	 if (state)
+	    init_c_cliptest();
+
+	 CHECK_EXTENSION(ARB_depth_clamp, cap);
+         FLUSH_VERTICES(ctx, _NEW_TRANSFORM);
+	 ctx->Transform.DepthClamp = state;
+	 break;
+
 #if FEATURE_ATI_fragment_shader
       case GL_FRAGMENT_SHADER_ATI:
         CHECK_EXTENSION(ATI_fragment_shader, cap);
@@ -1395,6 +1410,11 @@ _mesa_IsEnabled( GLenum cap )
          CHECK_EXTENSION(EXT_depth_bounds_test);
          return ctx->Depth.BoundsTest;
 
+      /* GL_ARB_depth_clamp */
+      case GL_DEPTH_CLAMP:
+         CHECK_EXTENSION(ARB_depth_clamp);
+         return ctx->Transform.DepthClamp;
+
 #if FEATURE_ATI_fragment_shader
       case GL_FRAGMENT_SHADER_ATI:
 	 CHECK_EXTENSION(ATI_fragment_shader);
diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index e3070b1547..ea67f820af 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -47,6 +47,7 @@ static const struct {
 } default_extensions[] = {
    { OFF, "GL_ARB_copy_buffer",                F(ARB_copy_buffer) },
    { OFF, "GL_ARB_depth_texture",              F(ARB_depth_texture) },
+   { OFF, "GL_ARB_depth_clamp",                F(ARB_depth_clamp) },
    { ON,  "GL_ARB_draw_buffers",               F(ARB_draw_buffers) },
    { OFF, "GL_ARB_fragment_program",           F(ARB_fragment_program) },
    { OFF, "GL_ARB_fragment_program_shadow",    F(ARB_fragment_program_shadow) },
@@ -192,6 +193,7 @@ void
 _mesa_enable_sw_extensions(GLcontext *ctx)
 {
    ctx->Extensions.ARB_copy_buffer = GL_TRUE;
+   ctx->Extensions.ARB_depth_clamp = GL_TRUE;
    ctx->Extensions.ARB_depth_texture = GL_TRUE;
    /*ctx->Extensions.ARB_draw_buffers = GL_TRUE;*/
 #if FEATURE_ARB_fragment_program
diff --git a/src/mesa/main/get_gen.py b/src/mesa/main/get_gen.py
index 2878c1b552..364d8c55c4 100644
--- a/src/mesa/main/get_gen.py
+++ b/src/mesa/main/get_gen.py
@@ -905,6 +905,10 @@ StateVars = [
 	  ["ctx->Depth.BoundsMin", "ctx->Depth.BoundsMax"],
 	  "", ["EXT_depth_bounds_test"] ),
 
+	# GL_ARB_depth_clamp
+	( "GL_DEPTH_CLAMP", GLboolean, ["ctx->Transform.DepthClamp"], "",
+	  ["ARB_depth_clamp"] ),
+
 	# GL_ARB_draw_buffers
 	( "GL_MAX_DRAW_BUFFERS_ARB", GLint,
 	  ["ctx->Const.MaxDrawBuffers"], "", None ),
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 6b64bf8139..20cd3aa5c0 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -1482,6 +1482,7 @@ struct gl_transform_attrib
    GLboolean Normalize;				/**< Normalize all normals? */
    GLboolean RescaleNormals;			/**< GL_EXT_rescale_normal */
    GLboolean RasterPositionUnclipped;           /**< GL_IBM_rasterpos_clip */
+   GLboolean DepthClamp;			/**< GL_ARB_depth_clamp */
 
    GLboolean CullVertexFlag;	/**< True if GL_CULL_VERTEX_EXT is enabled */
    GLfloat CullEyePos[4];
@@ -2475,6 +2476,7 @@ struct gl_extensions
    GLboolean dummy;  /* don't remove this! */
    GLboolean ARB_copy_buffer;
    GLboolean ARB_depth_texture;
+   GLboolean ARB_depth_clamp;
    GLboolean ARB_draw_buffers;
    GLboolean ARB_fragment_program;
    GLboolean ARB_fragment_program_shadow;