gallium: add interpolation parameter to simple shader functions

This lets us specify linear interpolation instead of perspective
interpolation for blit operations.  Might be a bit faster.

5 files changed, 56 insertions, 47 deletions

diff --git a/src/gallium/auxiliary/util/u_blit.c b/src/gallium/auxiliary/util/u_blit.c
index e9ee4ea760f..97fa99ec65d 100644
--- a/src/gallium/auxiliary/util/u_blit.c
+++ b/src/gallium/auxiliary/util/u_blit.c
@@ -134,7 +134,8 @@ util_create_blit(struct pipe_context *pipe, struct cso_context *cso)
 
    /* fragment shader */
    ctx->fs[TGSI_WRITEMASK_XYZW] =
-      util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_2D);
+      util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_2D,
+                                    TGSI_INTERPOLATE_LINEAR);
    ctx->vbuf = NULL;
 
    /* init vertex data that doesn't change */
@@ -474,6 +475,7 @@ util_blit_pixels_writemask(struct blit_state *ctx,
    if (ctx->fs[writemask] == NULL)
       ctx->fs[writemask] =
          util_make_fragment_tex_shader_writemask(pipe, TGSI_TEXTURE_2D,
+                                                 TGSI_INTERPOLATE_LINEAR,
                                                  writemask);
 
    /* shaders */
diff --git a/src/gallium/auxiliary/util/u_blitter.c b/src/gallium/auxiliary/util/u_blitter.c
index 1f3246208ba..bcd5686470b 100644
--- a/src/gallium/auxiliary/util/u_blitter.c
+++ b/src/gallium/auxiliary/util/u_blitter.c
@@ -516,6 +516,26 @@ void *blitter_get_fs_col(struct blitter_context_priv *ctx, unsigned num_cbufs)
    return ctx->fs_col[num_cbufs];
 }
 
+/** Convert PIPE_TEXTURE_x to TGSI_TEXTURE_x */
+static unsigned
+pipe_tex_to_tgsi_tex(unsigned pipe_tex_target)
+{
+   switch (pipe_tex_target) {
+   case PIPE_TEXTURE_1D:
+      return TGSI_TEXTURE_1D;
+   case PIPE_TEXTURE_2D:
+      return TGSI_TEXTURE_2D;
+   case PIPE_TEXTURE_3D:
+      return TGSI_TEXTURE_3D;
+   case PIPE_TEXTURE_CUBE:
+      return TGSI_TEXTURE_CUBE;
+   default:
+      assert(0 && "unexpected texture target");
+      return TGSI_TEXTURE_UNKNOWN;
+   }
+}
+
+
 static INLINE
 void *blitter_get_fs_texfetch_col(struct blitter_context_priv *ctx,
                                   unsigned tex_target)
@@ -526,25 +546,10 @@ void *blitter_get_fs_texfetch_col(struct blitter_context_priv *ctx,
 
    /* Create the fragment shader on-demand. */
    if (!ctx->fs_texfetch_col[tex_target]) {
-      switch (tex_target) {
-         case PIPE_TEXTURE_2D:
-            ctx->fs_texfetch_col[PIPE_TEXTURE_2D] =
-               util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_2D);
-            break;
-         case PIPE_TEXTURE_3D:
-            ctx->fs_texfetch_col[PIPE_TEXTURE_3D] =
-               util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_3D);
-            break;
-         case PIPE_TEXTURE_CUBE:
-            ctx->fs_texfetch_col[PIPE_TEXTURE_CUBE] =
-               util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_CUBE);
-            break;
-         case PIPE_TEXTURE_1D:
-         default:
-            ctx->fs_texfetch_col[PIPE_TEXTURE_1D] =
-               util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_1D);
-            tex_target = PIPE_TEXTURE_1D; /* for the default case */
-      }
+      unsigned tgsi_tex = pipe_tex_to_tgsi_tex(tex_target);
+
+      ctx->fs_texfetch_col[tex_target] =
+        util_make_fragment_tex_shader(pipe, tgsi_tex, TGSI_INTERPOLATE_LINEAR);
    }
 
    return ctx->fs_texfetch_col[tex_target];
@@ -560,25 +565,11 @@ void *blitter_get_fs_texfetch_depth(struct blitter_context_priv *ctx,
 
    /* Create the fragment shader on-demand. */
    if (!ctx->fs_texfetch_depth[tex_target]) {
-      switch (tex_target) {
-         case PIPE_TEXTURE_2D:
-            ctx->fs_texfetch_depth[PIPE_TEXTURE_2D] =
-               util_make_fragment_tex_shader_writedepth(pipe, TGSI_TEXTURE_2D);
-            break;
-         case PIPE_TEXTURE_3D:
-            ctx->fs_texfetch_depth[PIPE_TEXTURE_3D] =
-               util_make_fragment_tex_shader_writedepth(pipe, TGSI_TEXTURE_3D);
-            break;
-         case PIPE_TEXTURE_CUBE:
-            ctx->fs_texfetch_depth[PIPE_TEXTURE_CUBE] =
-               util_make_fragment_tex_shader_writedepth(pipe,TGSI_TEXTURE_CUBE);
-            break;
-         case PIPE_TEXTURE_1D:
-         default:
-            ctx->fs_texfetch_depth[PIPE_TEXTURE_1D] =
-               util_make_fragment_tex_shader_writedepth(pipe, TGSI_TEXTURE_1D);
-            tex_target = PIPE_TEXTURE_1D; /* for the default case */
-      }
+      unsigned tgsi_tex = pipe_tex_to_tgsi_tex(tex_target);
+
+      ctx->fs_texfetch_depth[tex_target] =
+         util_make_fragment_tex_shader_writedepth(pipe, tgsi_tex,
+                                                  TGSI_INTERPOLATE_LINEAR);
    }
 
    return ctx->fs_texfetch_depth[tex_target];
diff --git a/src/gallium/auxiliary/util/u_gen_mipmap.c b/src/gallium/auxiliary/util/u_gen_mipmap.c
index d19267be72f..b7fe2d3003a 100644
--- a/src/gallium/auxiliary/util/u_gen_mipmap.c
+++ b/src/gallium/auxiliary/util/u_gen_mipmap.c
@@ -1327,8 +1327,10 @@ util_create_gen_mipmap(struct pipe_context *pipe,
    }
 
    /* fragment shader */
-   ctx->fs2d = util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_2D);
-   ctx->fsCube = util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_CUBE);
+   ctx->fs2d = util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_2D,
+                                             TGSI_INTERPOLATE_LINEAR);
+   ctx->fsCube = util_make_fragment_tex_shader(pipe, TGSI_TEXTURE_CUBE,
+                                               TGSI_INTERPOLATE_LINEAR);
 
    /* vertex data that doesn't change */
    for (i = 0; i < 4; i++) {
diff --git a/src/gallium/auxiliary/util/u_simple_shaders.c b/src/gallium/auxiliary/util/u_simple_shaders.c
index 019dda767d0..5b682f496cb 100644
--- a/src/gallium/auxiliary/util/u_simple_shaders.c
+++ b/src/gallium/auxiliary/util/u_simple_shaders.c
@@ -87,10 +87,15 @@ util_make_vertex_passthrough_shader(struct pipe_context *pipe,
  *  MOV OUT[0], IMM[0]                    // (if writemask != 0xf)
  *  TEX OUT[0].writemask, IN[0], SAMP[0], 2D;
  *  END;
+ *
+ * \param tex_target  one of PIPE_TEXTURE_x
+ * \parma interp_mode  either TGSI_INTERPOLATE_LINEAR or PERSPECTIVE
+ * \param writemask  mask of TGSI_WRITEMASK_x
  */
 void *
 util_make_fragment_tex_shader_writemask(struct pipe_context *pipe,
                                         unsigned tex_target,
+                                        unsigned interp_mode,
                                         unsigned writemask )
 {
    struct ureg_program *ureg;
@@ -98,6 +103,9 @@ util_make_fragment_tex_shader_writemask(struct pipe_context *pipe,
    struct ureg_src tex;
    struct ureg_dst out;
 
+   assert(interp_mode == TGSI_INTERPOLATE_LINEAR ||
+          interp_mode == TGSI_INTERPOLATE_PERSPECTIVE);
+
    ureg = ureg_create( TGSI_PROCESSOR_FRAGMENT );
    if (ureg == NULL)
       return NULL;
@@ -106,7 +114,7 @@ util_make_fragment_tex_shader_writemask(struct pipe_context *pipe,
 
    tex = ureg_DECL_fs_input( ureg, 
                              TGSI_SEMANTIC_GENERIC, 0, 
-                             TGSI_INTERPOLATE_PERSPECTIVE );
+                             interp_mode );
 
    out = ureg_DECL_output( ureg, 
                            TGSI_SEMANTIC_COLOR,
@@ -133,10 +141,12 @@ util_make_fragment_tex_shader_writemask(struct pipe_context *pipe,
  * \param tex_target  one of PIPE_TEXTURE_x
  */
 void *
-util_make_fragment_tex_shader(struct pipe_context *pipe, unsigned tex_target )
+util_make_fragment_tex_shader(struct pipe_context *pipe, unsigned tex_target,
+                              unsigned interp_mode)
 {
    return util_make_fragment_tex_shader_writemask( pipe,
                                                    tex_target,
+                                                   interp_mode,
                                                    TGSI_WRITEMASK_XYZW );
 }
 
@@ -147,7 +157,8 @@ util_make_fragment_tex_shader(struct pipe_context *pipe, unsigned tex_target )
  */
 void *
 util_make_fragment_tex_shader_writedepth(struct pipe_context *pipe,
-                                         unsigned tex_target)
+                                         unsigned tex_target,
+                                         unsigned interp_mode)
 {
    struct ureg_program *ureg;
    struct ureg_src sampler;
@@ -163,7 +174,7 @@ util_make_fragment_tex_shader_writedepth(struct pipe_context *pipe,
 
    tex = ureg_DECL_fs_input( ureg,
                              TGSI_SEMANTIC_GENERIC, 0,
-                             TGSI_INTERPOLATE_PERSPECTIVE );
+                             interp_mode );
 
    out = ureg_DECL_output( ureg,
                            TGSI_SEMANTIC_COLOR,
diff --git a/src/gallium/auxiliary/util/u_simple_shaders.h b/src/gallium/auxiliary/util/u_simple_shaders.h
index 6e760942e25..4aa34bc4757 100644
--- a/src/gallium/auxiliary/util/u_simple_shaders.h
+++ b/src/gallium/auxiliary/util/u_simple_shaders.h
@@ -52,15 +52,18 @@ util_make_vertex_passthrough_shader(struct pipe_context *pipe,
 extern void *
 util_make_fragment_tex_shader_writemask(struct pipe_context *pipe, 
                                         unsigned tex_target,
+                                        unsigned interp_mode,
                                         unsigned writemask);
 
 extern void *
-util_make_fragment_tex_shader(struct pipe_context *pipe, unsigned tex_target);
+util_make_fragment_tex_shader(struct pipe_context *pipe, unsigned tex_target,
+                              unsigned interp_mode);
 
 
 extern void *
 util_make_fragment_tex_shader_writedepth(struct pipe_context *pipe,
-                                         unsigned tex_target);
+                                         unsigned tex_target,
+                                         unsigned interp_mode);
 
 
 extern void *