[Mesa-dev] [PATCH 3/3] mesa: replace GET_SHINE_TAB_ENTRY() macro with an inline function

[Brian Paul]

---
 src/mesa/main/light.h        |   32 +++++++++++++++++---------------
 src/mesa/tnl/t_rasterpos.c   |    3 +--
 src/mesa/tnl/t_vb_lighttmp.h |   27 +++++++--------------------
 3 files changed, 25 insertions(+), 37 deletions(-)

diff --git a/src/mesa/main/light.h b/src/mesa/main/light.h
index 26e604b..9966987 100644
--- a/src/mesa/main/light.h
+++ b/src/mesa/main/light.h
@@ -87,22 +87,24 @@ extern void
 _mesa_light(struct gl_context *ctx, GLuint lnum, GLenum pname, const GLfloat *params);
 
 
-/* Lerp between adjacent values in the f(x) lookup table, giving a
- * continuous function, with adequeate overall accuracy.  (Though
- * still pretty good compared to a straight lookup).
- * Result should be a GLfloat.
+/*
+ * Compute dp ^ SpecularExponent.
+ * Lerp between adjacent values in the f(x) lookup table, giving a
+ * continuous function, with adequate overall accuracy.  (Though still
+ * pretty good compared to a straight lookup).
  */
-#define GET_SHINE_TAB_ENTRY( table, dp, result )			\
-do {									\
-   struct gl_shine_tab *_tab = table;					\
-   float f = (dp * (SHINE_TABLE_SIZE-1));				\
-   int k = (int) f;							\
-   if (k < 0 /* gcc may cast an overflow float value to negative int value*/ \
-	|| k > SHINE_TABLE_SIZE-2)					\
-      result = (GLfloat) pow( dp, _tab->shininess );		\
-   else									\
-      result = _tab->tab[k] + (f-k)*(_tab->tab[k+1]-_tab->tab[k]);	\
-} while (0)
+static inline GLfloat
+_mesa_lookup_shininess(const struct gl_context *ctx, GLuint face, GLfloat dp)
+{
+   const struct gl_shine_tab *tab = ctx->_ShineTable[face];
+   float f = dp * (SHINE_TABLE_SIZE - 1);
+   int k = (int) f;
+   if (k < 0 /* gcc may cast an overflow float value to negative int value */
+	|| k > SHINE_TABLE_SIZE - 2)
+      return powf(dp, tab->shininess);
+   else
+      return tab->tab[k] + (f - k) * (tab->tab[k+1] - tab->tab[k]);
+}
 
 
 extern GLuint _mesa_material_bitmask( struct gl_context *ctx,
diff --git a/src/mesa/tnl/t_rasterpos.c b/src/mesa/tnl/t_rasterpos.c
index bdd6129..17611cd 100644
--- a/src/mesa/tnl/t_rasterpos.c
+++ b/src/mesa/tnl/t_rasterpos.c
@@ -214,8 +214,7 @@ shade_rastpos(struct gl_context *ctx,
 	 n_dot_h = DOT3(normal, h);
 
 	 if (n_dot_h > 0.0F) {
-	    GLfloat spec_coef;
-	    GET_SHINE_TAB_ENTRY( ctx->_ShineTable[0], n_dot_h, spec_coef );
+	    GLfloat spec_coef = _mesa_lookup_shininess(ctx, 0, n_dot_h);
 
 	    if (spec_coef > 1.0e-10) {
                if (ctx->Light.Model.ColorControl==GL_SEPARATE_SPECULAR_COLOR) {
diff --git a/src/mesa/tnl/t_vb_lighttmp.h b/src/mesa/tnl/t_vb_lighttmp.h
index 0b8c314..1041a24 100644
--- a/src/mesa/tnl/t_vb_lighttmp.h
+++ b/src/mesa/tnl/t_vb_lighttmp.h
@@ -204,10 +204,7 @@ static void TAG(light_rgba_spec)( struct gl_context *ctx,
 	 n_dot_h = correction * DOT3(normal, h);
 
 	 if (n_dot_h > 0.0F) {
-	    GLfloat spec_coef;
-	    struct gl_shine_tab *tab = ctx->_ShineTable[side];
-	    GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef );
-
+	    GLfloat spec_coef = _mesa_lookup_shininess(ctx, side, n_dot_h);
 	    if (spec_coef > 1.0e-10) {
 	       spec_coef *= attenuation;
 	       ACC_SCALE_SCALAR_3V( spec[side], spec_coef,
@@ -385,13 +382,8 @@ static void TAG(light_rgba)( struct gl_context *ctx,
 
 	    n_dot_h = correction * DOT3(normal, h);
 
-	    if (n_dot_h > 0.0F)
-	    {
-	       GLfloat spec_coef;
-	       struct gl_shine_tab *tab = ctx->_ShineTable[side];
-
-	       GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec_coef );
-
+	    if (n_dot_h > 0.0F) {
+	       GLfloat spec_coef = _mesa_lookup_shininess(ctx, side, n_dot_h);
 	       ACC_SCALE_SCALAR_3V( contrib, spec_coef,
 				    light->_MatSpecular[side]);
 	    }
@@ -491,8 +483,7 @@ static void TAG(light_fast_rgba_single)( struct gl_context *ctx,
          COPY_3V(sum, base[1]);
          ACC_SCALE_SCALAR_3V(sum, -n_dot_VP, light->_MatDiffuse[1]);
          if (n_dot_h > 0.0F) {
-            GLfloat spec;
-            GET_SHINE_TAB_ENTRY( ctx->_ShineTable[1], n_dot_h, spec );
+            GLfloat spec = _mesa_lookup_shininess(ctx, 1, n_dot_h);
             ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[1]);
          }
          COPY_3V(Bcolor[j], sum );
@@ -506,10 +497,8 @@ static void TAG(light_fast_rgba_single)( struct gl_context *ctx,
 	 COPY_3V(sum, base[0]);
 	 ACC_SCALE_SCALAR_3V(sum, n_dot_VP, light->_MatDiffuse[0]);
 	 if (n_dot_h > 0.0F) {
-	    GLfloat spec;
-	    GET_SHINE_TAB_ENTRY( ctx->_ShineTable[0], n_dot_h, spec );
+            GLfloat spec = _mesa_lookup_shininess(ctx, 0, n_dot_h);
 	    ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[0]);
-
 	 }
 	 COPY_3V(Fcolor[j], sum );
 	 Fcolor[j][3] = base[0][3];
@@ -600,8 +589,7 @@ static void TAG(light_fast_rgba)( struct gl_context *ctx,
 	    ACC_SCALE_SCALAR_3V(sum[0], n_dot_VP, light->_MatDiffuse[0]);
 	    n_dot_h = DOT3(normal, light->_h_inf_norm);
 	    if (n_dot_h > 0.0F) {
-	       struct gl_shine_tab *tab = ctx->_ShineTable[0];
-	       GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec );
+               spec = _mesa_lookup_shininess(ctx, 0, n_dot_h);
 	       ACC_SCALE_SCALAR_3V( sum[0], spec, light->_MatSpecular[0]);
 	    }
 	 }
@@ -610,8 +598,7 @@ static void TAG(light_fast_rgba)( struct gl_context *ctx,
 	    ACC_SCALE_SCALAR_3V(sum[1], -n_dot_VP, light->_MatDiffuse[1]);
 	    n_dot_h = -DOT3(normal, light->_h_inf_norm);
 	    if (n_dot_h > 0.0F) {
-	       struct gl_shine_tab *tab = ctx->_ShineTable[1];
-	       GET_SHINE_TAB_ENTRY( tab, n_dot_h, spec );
+               spec = _mesa_lookup_shininess(ctx, 1, n_dot_h);
 	       ACC_SCALE_SCALAR_3V( sum[1], spec, light->_MatSpecular[1]);
 	    }
 	 }
-- 
1.7.3.4