3 files changed, 32 insertions, 0 deletions
diff --git a/src/mesa/swrast/s_depth.c b/src/mesa/swrast/s_depth.c
index 26e23f02d59..1a428fb1a28 100644
--- a/src/mesa/swrast/s_depth.c
+++ b/src/mesa/swrast/s_depth.c
@@ -497,6 +497,33 @@ depth_test_span32( GLcontext *ctx, GLuint n,
    return passed;
 }
 
+/* Apply ARB_depth_clamp to span of fragments. */
+void
+_swrast_depth_clamp_span( GLcontext *ctx, SWspan *span )
+{
+   struct gl_framebuffer *fb = ctx->DrawBuffer;
+   struct gl_renderbuffer *rb = fb->_DepthBuffer;
+   const GLuint count = span->end;
+   GLuint *zValues = span->array->z;
+   GLuint near, far;
+   int i;
+
+   if (rb->DataType == GL_UNSIGNED_SHORT) {
+      near = FLOAT_TO_UINT(ctx->Viewport.Near);
+      far = FLOAT_TO_UINT(ctx->Viewport.Far);
+   } else {
+      assert(rb->DataType == GL_UNSIGNED_INT);
+      CLAMPED_FLOAT_TO_USHORT(near, ctx->Viewport.Near);
+      CLAMPED_FLOAT_TO_USHORT(far, ctx->Viewport.Far);
+   }
+   for (i = 0; i < count; i++) {
+      if (zValues[i] < near)
+	 zValues[i] = near;
+      if (zValues[i] > far)
+	 zValues[i] = far;
+   }
+}
+
 
 
 /*
diff --git a/src/mesa/swrast/s_depth.h b/src/mesa/swrast/s_depth.h
index 36886256830..7eae3667428 100644
--- a/src/mesa/swrast/s_depth.h
+++ b/src/mesa/swrast/s_depth.h
@@ -33,6 +33,8 @@
 extern GLuint
 _swrast_depth_test_span( GLcontext *ctx, SWspan *span);
 
+extern void
+_swrast_depth_clamp_span( GLcontext *ctx, SWspan *span );
 
 extern GLboolean
 _swrast_depth_bounds_test( GLcontext *ctx, SWspan *span );
diff --git a/src/mesa/swrast/s_span.c b/src/mesa/swrast/s_span.c
index 0e2793b4740..a45eac438e4 100644
--- a/src/mesa/swrast/s_span.c
+++ b/src/mesa/swrast/s_span.c
@@ -880,6 +880,9 @@ _swrast_write_index_span( GLcontext *ctx, SWspan *span)
       stipple_polygon_span(ctx, span);
    }
 
+   if (ctx->Transform.DepthClamp)
+      _swrast_depth_clamp_span(ctx, span);
+
    /* Stencil and Z testing */
    if (ctx->Stencil._Enabled || ctx->Depth.Test) {
       if (!(span->arrayMask & SPAN_Z))