mesa: Push the shine table into the tnl module.

All users of the shine table outside of the tnl module
are gone. Move the implementation into the tnl module and
prefix the public functions with _tnl.

Reviewed-by: Alex Deucher <alexdeucher@gmail.com>
Reviewed-by: Brian Paul <brianp@vmware.com>
Signed-off-by: Mathias Froehlich <Mathias.Froehlich@web.de>

5 files changed, 179 insertions, 9 deletions

diff --git a/src/mesa/tnl/t_context.c b/src/mesa/tnl/t_context.c
index 1ded44ccffb..ede1d742835 100644
--- a/src/mesa/tnl/t_context.c
+++ b/src/mesa/tnl/t_context.c
@@ -46,6 +46,7 @@ GLboolean
 _tnl_CreateContext( struct gl_context *ctx )
 {
    TNLcontext *tnl;
+   GLuint i;
 
    /* Create the TNLcontext structure
     */
@@ -76,10 +77,21 @@ _tnl_CreateContext( struct gl_context *ctx )
     */
    tnl->Driver.Render.PrimTabElts = _tnl_render_tab_elts;
    tnl->Driver.Render.PrimTabVerts = _tnl_render_tab_verts;
-   tnl->Driver.NotifyMaterialChange = _mesa_validate_all_lighting_tables;
+   tnl->Driver.NotifyMaterialChange = _tnl_validate_shine_tables;
 
    tnl->nr_blocks = 0;
 
+   /* Lighting miscellaneous */
+   tnl->_ShineTabList = MALLOC_STRUCT( tnl_shine_tab );
+   make_empty_list( tnl->_ShineTabList );
+   /* Allocate 10 (arbitrary) shininess lookup tables */
+   for (i = 0 ; i < 10 ; i++) {
+      struct tnl_shine_tab *s = MALLOC_STRUCT( tnl_shine_tab );
+      s->shininess = -1;
+      s->refcount = 0;
+      insert_at_tail( tnl->_ShineTabList, s );
+   }
+
    /* plug in the VBO drawing function */
    vbo_set_draw_func(ctx, _tnl_vbo_draw_prims);
 
@@ -93,8 +105,15 @@ _tnl_CreateContext( struct gl_context *ctx )
 void
 _tnl_DestroyContext( struct gl_context *ctx )
 {
+   struct tnl_shine_tab *s, *tmps;
    TNLcontext *tnl = TNL_CONTEXT(ctx);
 
+   /* Free lighting shininess exponentiation table */
+   foreach_s( s, tmps, tnl->_ShineTabList ) {
+      free( s );
+   }
+   free( tnl->_ShineTabList );
+
    _tnl_destroy_pipeline( ctx );
 
    FREE(tnl);
diff --git a/src/mesa/tnl/t_context.h b/src/mesa/tnl/t_context.h
index c5a902082b8..8f18ddeb17a 100644
--- a/src/mesa/tnl/t_context.h
+++ b/src/mesa/tnl/t_context.h
@@ -384,6 +384,20 @@ struct tnl_clipspace
 };
 
 
+#define SHINE_TABLE_SIZE 256	/**< Material shininess lookup table sizes */
+
+/**
+ * Material shininess lookup table.
+ */
+struct tnl_shine_tab
+{
+   struct tnl_shine_tab *next, *prev;
+   GLfloat tab[SHINE_TABLE_SIZE+1];
+   GLfloat shininess;
+   GLuint refcount;
+};
+
+
 struct tnl_device_driver
 {
    /***
@@ -518,6 +532,10 @@ typedef struct
    GLuint nr_blocks;
 
    GLuint CurInstance;
+
+   struct tnl_shine_tab *_ShineTable[2]; /**< Active shine tables */
+   struct tnl_shine_tab *_ShineTabList;  /**< MRU list of inactive shine tables */
+   /**@}*/
 } TNLcontext;
 
 
diff --git a/src/mesa/tnl/t_vb_light.c b/src/mesa/tnl/t_vb_light.c
index 3acedf6e577..39467fac731 100644
--- a/src/mesa/tnl/t_vb_light.c
+++ b/src/mesa/tnl/t_vb_light.c
@@ -36,6 +36,7 @@
 
 #include "t_context.h"
 #include "t_pipeline.h"
+#include "tnl.h"
 
 #define LIGHT_TWOSIDE       0x1
 #define LIGHT_MATERIAL      0x2
@@ -76,6 +77,114 @@ struct light_stage_data {
 
 
 
+/**********************************************************************/
+/*****                  Lighting computation                      *****/
+/**********************************************************************/
+
+
+/*
+ * Notes:
+ *   When two-sided lighting is enabled we compute the color (or index)
+ *   for both the front and back side of the primitive.  Then, when the
+ *   orientation of the facet is later learned, we can determine which
+ *   color (or index) to use for rendering.
+ *
+ *   KW: We now know orientation in advance and only shade for
+ *       the side or sides which are actually required.
+ *
+ * Variables:
+ *   n = normal vector
+ *   V = vertex position
+ *   P = light source position
+ *   Pe = (0,0,0,1)
+ *
+ * Precomputed:
+ *   IF P[3]==0 THEN
+ *       // light at infinity
+ *       IF local_viewer THEN
+ *           _VP_inf_norm = unit vector from V to P      // Precompute
+ *       ELSE
+ *           // eye at infinity
+ *           _h_inf_norm = Normalize( VP + <0,0,1> )     // Precompute
+ *       ENDIF
+ *   ENDIF
+ *
+ * Functions:
+ *   Normalize( v ) = normalized vector v
+ *   Magnitude( v ) = length of vector v
+ */
+
+
+
+static void
+validate_shine_table( struct gl_context *ctx, GLuint side, GLfloat shininess )
+{
+   TNLcontext *tnl = TNL_CONTEXT(ctx);
+   struct tnl_shine_tab *list = tnl->_ShineTabList;
+   struct tnl_shine_tab *s;
+
+   ASSERT(side < 2);
+
+   foreach(s, list)
+      if ( s->shininess == shininess )
+	 break;
+
+   if (s == list) {
+      GLint j;
+      GLfloat *m;
+
+      foreach(s, list)
+	 if (s->refcount == 0)
+	    break;
+
+      m = s->tab;
+      m[0] = 0.0;
+      if (shininess == 0.0) {
+	 for (j = 1 ; j <= SHINE_TABLE_SIZE ; j++)
+	    m[j] = 1.0;
+      }
+      else {
+	 for (j = 1 ; j < SHINE_TABLE_SIZE ; j++) {
+            GLdouble t, x = j / (GLfloat) (SHINE_TABLE_SIZE - 1);
+            if (x < 0.005) /* underflow check */
+               x = 0.005;
+            t = pow(x, shininess);
+	    if (t > 1e-20)
+	       m[j] = (GLfloat) t;
+	    else
+	       m[j] = 0.0;
+	 }
+	 m[SHINE_TABLE_SIZE] = 1.0;
+      }
+
+      s->shininess = shininess;
+   }
+
+   if (tnl->_ShineTable[side])
+      tnl->_ShineTable[side]->refcount--;
+
+   tnl->_ShineTable[side] = s;
+   move_to_tail( list, s );
+   s->refcount++;
+}
+
+
+void
+_tnl_validate_shine_tables( struct gl_context *ctx )
+{
+   TNLcontext *tnl = TNL_CONTEXT(ctx);
+   GLfloat shininess;
+   
+   shininess = ctx->Light.Material.Attrib[MAT_ATTRIB_FRONT_SHININESS][0];
+   if (!tnl->_ShineTable[0] || tnl->_ShineTable[0]->shininess != shininess)
+      validate_shine_table( ctx, 0, shininess );
+
+   shininess = ctx->Light.Material.Attrib[MAT_ATTRIB_BACK_SHININESS][0];
+   if (!tnl->_ShineTable[1] || tnl->_ShineTable[1]->shininess != shininess)
+      validate_shine_table( ctx, 1, shininess );
+}
+
+
 /**
  * In the case of colormaterial, the effected material attributes
  * should already have been bound to point to the incoming color data,
@@ -101,7 +210,7 @@ update_materials(struct gl_context *ctx, struct light_stage_data *store)
    /* XXX we should only call this if we're tracking/changing the specular
     * exponent.
     */
-   _mesa_validate_all_lighting_tables( ctx );
+   _tnl_validate_shine_tables( ctx );
 }
 
 
@@ -149,11 +258,32 @@ prepare_materials(struct gl_context *ctx,
    /* FIXME: Is this already done?
     */
    _mesa_update_material( ctx, ~0 );
-   _mesa_validate_all_lighting_tables( ctx );
+
+   _tnl_validate_shine_tables( ctx );
 
    return store->mat_count;
 }
 
+/*
+ * 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).
+ */
+static inline GLfloat
+lookup_shininess(const struct gl_context *ctx, GLuint face, GLfloat dp)
+{
+   TNLcontext *tnl = TNL_CONTEXT(ctx);
+   const struct tnl_shine_tab *tab = tnl->_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]);
+}
+
 /* Tables for all the shading functions.
  */
 static light_func _tnl_light_tab[MAX_LIGHT_FUNC];
diff --git a/src/mesa/tnl/t_vb_lighttmp.h b/src/mesa/tnl/t_vb_lighttmp.h
index 1041a24e761..1944e5ddc6d 100644
--- a/src/mesa/tnl/t_vb_lighttmp.h
+++ b/src/mesa/tnl/t_vb_lighttmp.h
@@ -204,7 +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 = _mesa_lookup_shininess(ctx, side, n_dot_h);
+	    GLfloat spec_coef = lookup_shininess(ctx, side, n_dot_h);
 	    if (spec_coef > 1.0e-10) {
 	       spec_coef *= attenuation;
 	       ACC_SCALE_SCALAR_3V( spec[side], spec_coef,
@@ -383,7 +383,7 @@ 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 = _mesa_lookup_shininess(ctx, side, n_dot_h);
+	       GLfloat spec_coef = lookup_shininess(ctx, side, n_dot_h);
 	       ACC_SCALE_SCALAR_3V( contrib, spec_coef,
 				    light->_MatSpecular[side]);
 	    }
@@ -483,7 +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 = _mesa_lookup_shininess(ctx, 1, n_dot_h);
+            GLfloat spec = lookup_shininess(ctx, 1, n_dot_h);
             ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[1]);
          }
          COPY_3V(Bcolor[j], sum );
@@ -497,7 +497,7 @@ 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 = _mesa_lookup_shininess(ctx, 0, n_dot_h);
+            GLfloat spec = lookup_shininess(ctx, 0, n_dot_h);
 	    ACC_SCALE_SCALAR_3V(sum, spec, light->_MatSpecular[0]);
 	 }
 	 COPY_3V(Fcolor[j], sum );
@@ -589,7 +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) {
-               spec = _mesa_lookup_shininess(ctx, 0, n_dot_h);
+               spec = lookup_shininess(ctx, 0, n_dot_h);
 	       ACC_SCALE_SCALAR_3V( sum[0], spec, light->_MatSpecular[0]);
 	    }
 	 }
@@ -598,7 +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) {
-               spec = _mesa_lookup_shininess(ctx, 1, n_dot_h);
+               spec = lookup_shininess(ctx, 1, n_dot_h);
 	       ACC_SCALE_SCALAR_3V( sum[1], spec, light->_MatSpecular[1]);
 	    }
 	 }
diff --git a/src/mesa/tnl/tnl.h b/src/mesa/tnl/tnl.h
index d3889811e21..434bd7fcd95 100644
--- a/src/mesa/tnl/tnl.h
+++ b/src/mesa/tnl/tnl.h
@@ -101,4 +101,7 @@ _mesa_load_tracked_matrices(struct gl_context *ctx);
 extern void
 _tnl_RasterPos(struct gl_context *ctx, const GLfloat vObj[4]);
 
+extern void
+_tnl_validate_shine_tables( struct gl_context *ctx );
+
 #endif