Mesa (master): i965: Refactor texture swizzle generation into a helper.

[Kenneth Graunke]

Module: Mesa
Branch: master
Commit: b5a042a657fed45264406cbd0d67fa6217a410a1
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=b5a042a657fed45264406cbd0d67fa6217a410a1

Author: Kenneth Graunke <kenneth at whitecape.org>
Date:   Fri Sep  7 13:24:16 2012 -0700

i965: Refactor texture swizzle generation into a helper.

It's going to be reused in a second place soon.

Reviewed-by: Eric Anholt <eric at anholt.net>
Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>

---

 src/mesa/drivers/dri/i965/brw_state.h            |    2 +
 src/mesa/drivers/dri/i965/brw_wm.c               |   51 +-------------------
 src/mesa/drivers/dri/i965/brw_wm_surface_state.c |   56 ++++++++++++++++++++++
 3 files changed, 60 insertions(+), 49 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_state.h b/src/mesa/drivers/dri/i965/brw_state.h
index 99fa088..48dd4ba 100644
--- a/src/mesa/drivers/dri/i965/brw_state.h
+++ b/src/mesa/drivers/dri/i965/brw_state.h
@@ -202,6 +202,8 @@ GLuint translate_tex_format(gl_format mesa_format,
 			    GLenum depth_mode,
 			    GLenum srgb_decode);
 
+int brw_get_texture_swizzle(const struct gl_texture_object *t);
+
 /* gen7_wm_surface_state.c */
 void gen7_set_surface_tiling(struct gen7_surface_state *surf, uint32_t tiling);
 void gen7_set_surface_msaa(struct gen7_surface_state *surf,
diff --git a/src/mesa/drivers/dri/i965/brw_wm.c b/src/mesa/drivers/dri/i965/brw_wm.c
index 995e8f3..0f11525 100644
--- a/src/mesa/drivers/dri/i965/brw_wm.c
+++ b/src/mesa/drivers/dri/i965/brw_wm.c
@@ -504,49 +504,8 @@ brw_populate_sampler_prog_key_data(struct gl_context *ctx,
 	 const struct gl_texture_object *t = unit->_Current;
 	 const struct gl_texture_image *img = t->Image[0][t->BaseLevel];
 	 struct gl_sampler_object *sampler = _mesa_get_samplerobj(ctx, unit_id);
-	 int swizzles[SWIZZLE_NIL + 1] = {
-	    SWIZZLE_X,
-	    SWIZZLE_Y,
-	    SWIZZLE_Z,
-	    SWIZZLE_W,
-	    SWIZZLE_ZERO,
-	    SWIZZLE_ONE,
-	    SWIZZLE_NIL
-	 };
-
-	 if (img->_BaseFormat == GL_DEPTH_COMPONENT ||
-	     img->_BaseFormat == GL_DEPTH_STENCIL) {
-	    /* We handle GL_DEPTH_TEXTURE_MODE here instead of as surface
-	     * format overrides because shadow comparison always returns the
-	     * result of the comparison in all channels anyway.
-	     */
-	    switch (t->DepthMode) {
-	    case GL_ALPHA:
-	       swizzles[0] = SWIZZLE_ZERO;
-	       swizzles[1] = SWIZZLE_ZERO;
-	       swizzles[2] = SWIZZLE_ZERO;
-	       swizzles[3] = SWIZZLE_X;
-	       break;
-	    case GL_LUMINANCE:
-	       swizzles[0] = SWIZZLE_X;
-	       swizzles[1] = SWIZZLE_X;
-	       swizzles[2] = SWIZZLE_X;
-	       swizzles[3] = SWIZZLE_ONE;
-	       break;
-	    case GL_INTENSITY:
-	       swizzles[0] = SWIZZLE_X;
-	       swizzles[1] = SWIZZLE_X;
-	       swizzles[2] = SWIZZLE_X;
-	       swizzles[3] = SWIZZLE_X;
-	       break;
-	    case GL_RED:
-	       swizzles[0] = SWIZZLE_X;
-	       swizzles[1] = SWIZZLE_ZERO;
-	       swizzles[2] = SWIZZLE_ZERO;
-	       swizzles[3] = SWIZZLE_ONE;
-	       break;
-	    }
-	 }
+
+	 key->swizzles[s] = brw_get_texture_swizzle(t);
 
 	 if (img->InternalFormat == GL_YCBCR_MESA) {
 	    key->yuvtex_mask |= 1 << s;
@@ -554,12 +513,6 @@ brw_populate_sampler_prog_key_data(struct gl_context *ctx,
 		key->yuvtex_swap_mask |= 1 << s;
 	 }
 
-	 key->swizzles[s] =
-	    MAKE_SWIZZLE4(swizzles[GET_SWZ(t->_Swizzle, 0)],
-			  swizzles[GET_SWZ(t->_Swizzle, 1)],
-			  swizzles[GET_SWZ(t->_Swizzle, 2)],
-			  swizzles[GET_SWZ(t->_Swizzle, 3)]);
-
 	 if (sampler->MinFilter != GL_NEAREST &&
 	     sampler->MagFilter != GL_NEAREST) {
 	    if (sampler->WrapS == GL_CLAMP)
diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
index 582e239..abdcb84 100644
--- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
@@ -653,6 +653,62 @@ brw_get_surface_num_multisamples(unsigned num_samples)
 }
 
 
+/**
+ * Compute the combination of DEPTH_TEXTURE_MODE and EXT_texture_swizzle
+ * swizzling.
+ */
+int
+brw_get_texture_swizzle(const struct gl_texture_object *t)
+{
+   const struct gl_texture_image *img = t->Image[0][t->BaseLevel];
+
+   int swizzles[SWIZZLE_NIL + 1] = {
+      SWIZZLE_X,
+      SWIZZLE_Y,
+      SWIZZLE_Z,
+      SWIZZLE_W,
+      SWIZZLE_ZERO,
+      SWIZZLE_ONE,
+      SWIZZLE_NIL
+   };
+
+   if (img->_BaseFormat == GL_DEPTH_COMPONENT ||
+       img->_BaseFormat == GL_DEPTH_STENCIL) {
+      switch (t->DepthMode) {
+      case GL_ALPHA:
+         swizzles[0] = SWIZZLE_ZERO;
+         swizzles[1] = SWIZZLE_ZERO;
+         swizzles[2] = SWIZZLE_ZERO;
+         swizzles[3] = SWIZZLE_X;
+         break;
+      case GL_LUMINANCE:
+         swizzles[0] = SWIZZLE_X;
+         swizzles[1] = SWIZZLE_X;
+         swizzles[2] = SWIZZLE_X;
+         swizzles[3] = SWIZZLE_ONE;
+         break;
+      case GL_INTENSITY:
+         swizzles[0] = SWIZZLE_X;
+         swizzles[1] = SWIZZLE_X;
+         swizzles[2] = SWIZZLE_X;
+         swizzles[3] = SWIZZLE_X;
+         break;
+      case GL_RED:
+         swizzles[0] = SWIZZLE_X;
+         swizzles[1] = SWIZZLE_ZERO;
+         swizzles[2] = SWIZZLE_ZERO;
+         swizzles[3] = SWIZZLE_ONE;
+         break;
+      }
+   }
+
+   return MAKE_SWIZZLE4(swizzles[GET_SWZ(t->_Swizzle, 0)],
+                        swizzles[GET_SWZ(t->_Swizzle, 1)],
+                        swizzles[GET_SWZ(t->_Swizzle, 2)],
+                        swizzles[GET_SWZ(t->_Swizzle, 3)]);
+}
+
+
 static void
 brw_update_buffer_texture_surface(struct gl_context *ctx,
                                   unsigned unit,