Removed all RCS / CVS tags (Id, Header, Date, etc.) from everything.
[mesa.git] / src / mesa / swrast / s_tritemp.h
index e139f3fc9f96c2e4fab471edc3c9a0058da97f6b..97060285e5d3fde4159cb59e0fd5fcaa321d5342 100644 (file)
@@ -1,21 +1,19 @@
-/* $Id: s_tritemp.h,v 1.7 2001/01/23 23:39:37 brianp Exp $ */
-
 /*
  * Mesa 3-D graphics library
- * Version:  3.5
- * 
- * Copyright (C) 1999-2000  Brian Paul   All Rights Reserved.
- * 
+ * Version:  5.1
+ *
+ * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
+ *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
  * to deal in the Software without restriction, including without limitation
  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  * and/or sell copies of the Software, and to permit persons to whom the
  * Software is furnished to do so, subject to the following conditions:
- * 
+ *
  * The above copyright notice and this permission notice shall be included
  * in all copies or substantial portions of the Software.
- * 
+ *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
@@ -24,7 +22,6 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-
 /*
  * Triangle Rasterizer Template
  *
  * The following macros may be defined to indicate what auxillary information
  * must be interplated across the triangle:
  *    INTERP_Z        - if defined, interpolate Z values
+ *    INTERP_FOG      - if defined, interpolate fog values
  *    INTERP_RGB      - if defined, interpolate RGB values
+ *    INTERP_ALPHA    - if defined, interpolate Alpha values (req's INTERP_RGB)
  *    INTERP_SPEC     - if defined, interpolate specular RGB values
- *    INTERP_ALPHA    - if defined, interpolate Alpha values
  *    INTERP_INDEX    - if defined, interpolate color index values
  *    INTERP_INT_TEX  - if defined, interpolate integer ST texcoords
  *                         (fast, simple 2-D texture mapping)
  *
  * Optionally, one may provide one-time setup code per triangle:
  *    SETUP_CODE    - code which is to be executed once per triangle
- * 
- * The following macro MUST be defined:
- *    INNER_LOOP(LEFT,RIGHT,Y) - code to write a span of pixels.
- *        Something like:
+ *    CLEANUP_CODE    - code to execute at end of triangle
  *
- *                    for (x=LEFT; x<RIGHT;x++) {
- *                       put_pixel(x,Y);
- *                       // increment fixed point interpolants
- *                    }
+ * The following macro MUST be defined:
+ *    RENDER_SPAN(span) - code to write a span of pixels.
  *
  * This code was designed for the origin to be in the lower-left corner.
  *
  */
 
 
-/*void triangle( GLcontext *ctx, SWvertex *v0, SWvertex *v1, SWvertex *v2 )*/
+/*
+ * ColorTemp is used for intermediate color values.
+ */
+#if CHAN_TYPE == GL_FLOAT
+#define ColorTemp GLfloat
+#else
+#define ColorTemp GLint  /* same as GLfixed */
+#endif
+
+/*
+ * Either loop over all texture units, or just use unit zero.
+ */
+#ifdef INTERP_MULTITEX
+#define TEX_UNIT_LOOP(CODE)                                    \
+   {                                                           \
+      GLuint u;                                                        \
+      for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {       \
+         if (ctx->Texture._EnabledCoordUnits & (1 << u)) {     \
+            CODE                                               \
+         }                                                     \
+      }                                                                \
+   }
+#define INTERP_TEX
+#elif defined(INTERP_TEX)
+#define TEX_UNIT_LOOP(CODE)                                    \
+   {                                                           \
+      const GLuint u = 0;                                      \
+      CODE                                                     \
+   }
+#endif
+
+
+static void NAME(GLcontext *ctx, const SWvertex *v0,
+                                 const SWvertex *v1,
+                                 const SWvertex *v2 )
 {
    typedef struct {
         const SWvertex *v0, *v1;   /* Y(v0) < Y(v1) */
-       GLfloat dx;     /* X(v1) - X(v0) */
-       GLfloat dy;     /* Y(v1) - Y(v0) */
-       GLfixed fdxdy;  /* dx/dy in fixed-point */
-       GLfixed fsx;    /* first sample point x coord */
-       GLfixed fsy;
-       GLfloat adjy;   /* adjust from v[0]->fy to fsy, scaled */
-       GLint lines;    /* number of lines to be sampled on this edge */
-       GLfixed fx0;    /* fixed pt X of lower endpoint */
+        GLfloat dx;    /* X(v1) - X(v0) */
+        GLfloat dy;    /* Y(v1) - Y(v0) */
+        GLfixed fdxdy; /* dx/dy in fixed-point */
+        GLfixed fsx;   /* first sample point x coord */
+        GLfixed fsy;
+        GLfloat adjy;  /* adjust from v[0]->fy to fsy, scaled */
+        GLint lines;   /* number of lines to be sampled on this edge */
+        GLfixed fx0;   /* fixed pt X of lower endpoint */
    } EdgeT;
 
 #ifdef INTERP_Z
    GLfloat oneOverArea;
    const SWvertex *vMin, *vMid, *vMax;  /* Y(vMin)<=Y(vMid)<=Y(vMax) */
    float bf = SWRAST_CONTEXT(ctx)->_backface_sign;
+   const GLint snapMask = ~((FIXED_ONE / (1 << SUB_PIXEL_BITS)) - 1); /* for x/y coord snapping */
+   GLfixed vMin_fx, vMin_fy, vMid_fx, vMid_fy, vMax_fx, vMax_fy;
+
+   struct sw_span span;
+
+   INIT_SPAN(span, GL_POLYGON, 0, 0, 0);
+
+#ifdef INTERP_Z
+   (void) fixedToDepthShift;
+#endif
 
-   /* find the order of the 3 vertices along the Y axis */
+   /*
+   printf("%s()\n", __FUNCTION__);
+   printf("  %g, %g, %g\n", v0->win[0], v0->win[1], v0->win[2]);
+   printf("  %g, %g, %g\n", v1->win[0], v1->win[1], v1->win[2]);
+   printf("  %g, %g, %g\n", v2->win[0], v2->win[1], v2->win[2]);
+   */
+
+   /* Compute fixed point x,y coords w/ half-pixel offsets and snapping.
+    * And find the order of the 3 vertices along the Y axis.
+    */
    {
-      GLfloat y0 = v0->win[1];
-      GLfloat y1 = v1->win[1];
-      GLfloat y2 = v2->win[1];
-
-      if (y0<=y1) {
-        if (y1<=y2) {
-           vMin = v0;   vMid = v1;   vMax = v2;   /* y0<=y1<=y2 */
-        }
-        else if (y2<=y0) {
-           vMin = v2;   vMid = v0;   vMax = v1;   /* y2<=y0<=y1 */
-        }
-        else {
-           vMin = v0;   vMid = v2;   vMax = v1;  bf = -bf; /* y0<=y2<=y1 */
-        }
+      const GLfixed fy0 = FloatToFixed(v0->win[1] - 0.5F) & snapMask;
+      const GLfixed fy1 = FloatToFixed(v1->win[1] - 0.5F) & snapMask;
+      const GLfixed fy2 = FloatToFixed(v2->win[1] - 0.5F) & snapMask;
+
+      if (fy0 <= fy1) {
+         if (fy1 <= fy2) {
+            /* y0 <= y1 <= y2 */
+            vMin = v0;   vMid = v1;   vMax = v2;
+            vMin_fy = fy0;  vMid_fy = fy1;  vMax_fy = fy2;
+         }
+         else if (fy2 <= fy0) {
+            /* y2 <= y0 <= y1 */
+            vMin = v2;   vMid = v0;   vMax = v1;
+            vMin_fy = fy2;  vMid_fy = fy0;  vMax_fy = fy1;
+         }
+         else {
+            /* y0 <= y2 <= y1 */
+            vMin = v0;   vMid = v2;   vMax = v1;
+            vMin_fy = fy0;  vMid_fy = fy2;  vMax_fy = fy1;
+            bf = -bf;
+         }
       }
       else {
-        if (y0<=y2) {
-           vMin = v1;   vMid = v0;   vMax = v2;  bf = -bf; /* y1<=y0<=y2 */
-        }
-        else if (y2<=y1) {
-           vMin = v2;   vMid = v1;   vMax = v0;  bf = -bf; /* y2<=y1<=y0 */
-        }
-        else {
-           vMin = v1;   vMid = v2;   vMax = v0;   /* y1<=y2<=y0 */
-        }
+         if (fy0 <= fy2) {
+            /* y1 <= y0 <= y2 */
+            vMin = v1;   vMid = v0;   vMax = v2;
+            vMin_fy = fy1;  vMid_fy = fy0;  vMax_fy = fy2;
+            bf = -bf;
+         }
+         else if (fy2 <= fy1) {
+            /* y2 <= y1 <= y0 */
+            vMin = v2;   vMid = v1;   vMax = v0;
+            vMin_fy = fy2;  vMid_fy = fy1;  vMax_fy = fy0;
+            bf = -bf;
+         }
+         else {
+            /* y1 <= y2 <= y0 */
+            vMin = v1;   vMid = v2;   vMax = v0;
+            vMin_fy = fy1;  vMid_fy = fy2;  vMax_fy = fy0;
+         }
       }
+
+      /* fixed point X coords */
+      vMin_fx = FloatToFixed(vMin->win[0] + 0.5F) & snapMask;
+      vMid_fx = FloatToFixed(vMid->win[0] + 0.5F) & snapMask;
+      vMax_fx = FloatToFixed(vMax->win[0] + 0.5F) & snapMask;
    }
 
    /* vertex/edge relationship */
    eTop.v0 = vMid;   eTop.v1 = vMax;
    eBot.v0 = vMin;   eBot.v1 = vMid;
 
-   /* compute deltas for each edge:  vertex[v1] - vertex[v0] */
-   eMaj.dx = vMax->win[0] - vMin->win[0];
-   eMaj.dy = vMax->win[1] - vMin->win[1];
-   eTop.dx = vMax->win[0] - vMid->win[0];
-   eTop.dy = vMax->win[1] - vMid->win[1];
-   eBot.dx = vMid->win[0] - vMin->win[0];
-   eBot.dy = vMid->win[1] - vMin->win[1];
+   /* compute deltas for each edge:  vertex[upper] - vertex[lower] */
+   eMaj.dx = FixedToFloat(vMax_fx - vMin_fx);
+   eMaj.dy = FixedToFloat(vMax_fy - vMin_fy);
+   eTop.dx = FixedToFloat(vMax_fx - vMid_fx);
+   eTop.dy = FixedToFloat(vMax_fy - vMid_fy);
+   eBot.dx = FixedToFloat(vMid_fx - vMin_fx);
+   eBot.dy = FixedToFloat(vMid_fy - vMin_fy);
 
-   /* compute oneOverArea */
+   /* compute area, oneOverArea and perform backface culling */
    {
       const GLfloat area = eMaj.dx * eBot.dy - eBot.dx * eMaj.dy;
 
       /* Do backface culling */
       if (area * bf < 0.0)
-        return;
+         return;
 
-      if (area == 0.0F)
+      if (IS_INF_OR_NAN(area) || area == 0.0F)
          return;
 
-      /* check for very tiny triangle */
-      if (area * area < (0.05F * 0.05F))  /* square to ensure positive value */
-         oneOverArea = 1.0F / 0.05F;  /* a close-enough value */
-      else
-         oneOverArea = 1.0F / area;
+      oneOverArea = 1.0F / area;
    }
 
 #ifndef DO_OCCLUSION_TEST
    ctx->OcclusionResult = GL_TRUE;
 #endif
+   span.facing = ctx->_Facing; /* for 2-sided stencil test */
 
    /* Edge setup.  For a triangle strip these could be reused... */
    {
-      /* fixed point Y coordinates */
-      GLfixed vMin_fx = FloatToFixed(vMin->win[0] + 0.5F);
-      GLfixed vMin_fy = FloatToFixed(vMin->win[1] - 0.5F);
-      GLfixed vMid_fx = FloatToFixed(vMid->win[0] + 0.5F);
-      GLfixed vMid_fy = FloatToFixed(vMid->win[1] - 0.5F);
-      GLfixed vMax_fy = FloatToFixed(vMax->win[1] - 0.5F);
-
       eMaj.fsy = FixedCeil(vMin_fy);
       eMaj.lines = FixedToInt(FixedCeil(vMax_fy - eMaj.fsy));
       if (eMaj.lines > 0) {
     * By stepping rasterization parameters along the major edge,
     * we can avoid recomputing them at the discontinuity where
     * the top and bottom edges meet.  However, this forces us to
-    * be able to scan both left-to-right and right-to-left. 
+    * be able to scan both left-to-right and right-to-left.
     * Also, we must determine whether the major edge is at the
     * left or right side of the triangle.  We do this by
     * computing the magnitude of the cross-product of the major
     */
 
    {
-      GLint ltor;              /* true if scanning left-to-right */
-#ifdef INTERP_Z
-      GLfloat dzdx, dzdy;      GLfixed fdzdx;
-      GLfloat dfogdx, dfogdy;      GLfixed fdfogdx;
-#endif
-#ifdef INTERP_RGB
-      GLfloat drdx, drdy;      GLfixed fdrdx;
-      GLfloat dgdx, dgdy;      GLfixed fdgdx;
-      GLfloat dbdx, dbdy;      GLfixed fdbdx;
-#endif
-#ifdef INTERP_SPEC
-      GLfloat dsrdx, dsrdy;    GLfixed fdsrdx;
-      GLfloat dsgdx, dsgdy;    GLfixed fdsgdx;
-      GLfloat dsbdx, dsbdy;    GLfixed fdsbdx;
-#endif
-#ifdef INTERP_ALPHA
-      GLfloat dadx, dady;      GLfixed fdadx;
-#endif
+      GLint scan_from_left_to_right;  /* true if scanning left-to-right */
 #ifdef INTERP_INDEX
-      GLfloat didx, didy;      GLfixed fdidx;
-#endif
-#ifdef INTERP_INT_TEX
-      GLfloat dsdx, dsdy;      GLfixed fdsdx;
-      GLfloat dtdx, dtdy;      GLfixed fdtdx;
-#endif
-#ifdef INTERP_TEX
-      GLfloat dsdx, dsdy;
-      GLfloat dtdx, dtdy;
-      GLfloat dudx, dudy;
-      GLfloat dvdx, dvdy;
-#endif
-#ifdef INTERP_MULTITEX
-      GLfloat dsdx[MAX_TEXTURE_UNITS], dsdy[MAX_TEXTURE_UNITS];
-      GLfloat dtdx[MAX_TEXTURE_UNITS], dtdy[MAX_TEXTURE_UNITS];
-      GLfloat dudx[MAX_TEXTURE_UNITS], dudy[MAX_TEXTURE_UNITS];
-      GLfloat dvdx[MAX_TEXTURE_UNITS], dvdy[MAX_TEXTURE_UNITS];
+      GLfloat didx, didy;
 #endif
 
       /*
       SETUP_CODE
 #endif
 
-      ltor = (oneOverArea < 0.0F);
+      scan_from_left_to_right = (oneOverArea < 0.0F);
+
 
       /* compute d?/dx and d?/dy derivatives */
 #ifdef INTERP_Z
+      span.interpMask |= SPAN_Z;
       {
-         GLfloat eMaj_dz, eBot_dz;
-         eMaj_dz = vMax->win[2] - vMin->win[2];
-         eBot_dz = vMid->win[2] - vMin->win[2];
-         dzdx = oneOverArea * (eMaj_dz * eBot.dy - eMaj.dy * eBot_dz);
-         if (dzdx > maxDepth || dzdx < -maxDepth) {
+         GLfloat eMaj_dz = vMax->win[2] - vMin->win[2];
+         GLfloat eBot_dz = vMid->win[2] - vMin->win[2];
+         span.dzdx = oneOverArea * (eMaj_dz * eBot.dy - eMaj.dy * eBot_dz);
+         if (span.dzdx > maxDepth || span.dzdx < -maxDepth) {
             /* probably a sliver triangle */
-            dzdx = 0.0;
-            dzdy = 0.0;
+            span.dzdx = 0.0;
+            span.dzdy = 0.0;
          }
          else {
-            dzdy = oneOverArea * (eMaj.dx * eBot_dz - eMaj_dz * eBot.dx);
+            span.dzdy = oneOverArea * (eMaj.dx * eBot_dz - eMaj_dz * eBot.dx);
          }
          if (depthBits <= 16)
-            fdzdx = SignedFloatToFixed(dzdx);
+            span.zStep = SignedFloatToFixed(span.dzdx);
          else
-            fdzdx = (GLint) dzdx;
-      }
-      {
-         GLfloat eMaj_dfog, eBot_dfog;
-         eMaj_dfog = (vMax->fog - vMin->fog) * 256;
-         eBot_dfog = (vMid->fog - vMin->fog) * 256;
-         dfogdx = oneOverArea * (eMaj_dfog * eBot.dy - eMaj.dy * eBot_dfog);
-         fdfogdx = SignedFloatToFixed(dfogdx);
-         dfogdy = oneOverArea * (eMaj.dx * eBot_dfog - eMaj_dfog * eBot.dx);
+            span.zStep = (GLint) span.dzdx;
       }
 #endif
-#ifdef INTERP_RGB
-      {
-         GLfloat eMaj_dr, eBot_dr;
-         eMaj_dr = (GLint) vMax->color[0]
-                 - (GLint) vMin->color[0];
-         eBot_dr = (GLint) vMid->color[0]
-                 - (GLint) vMin->color[0];
-         drdx = oneOverArea * (eMaj_dr * eBot.dy - eMaj.dy * eBot_dr);
-         fdrdx = SignedFloatToFixed(drdx);
-         drdy = oneOverArea * (eMaj.dx * eBot_dr - eMaj_dr * eBot.dx);
-      }
+#ifdef INTERP_W
       {
-         GLfloat eMaj_dg, eBot_dg;
-         eMaj_dg = (GLint) vMax->color[1]
-                 - (GLint) vMin->color[1];
-        eBot_dg = (GLint) vMid->color[1]
-                 - (GLint) vMin->color[1];
-         dgdx = oneOverArea * (eMaj_dg * eBot.dy - eMaj.dy * eBot_dg);
-         fdgdx = SignedFloatToFixed(dgdx);
-         dgdy = oneOverArea * (eMaj.dx * eBot_dg - eMaj_dg * eBot.dx);
+         const GLfloat eMaj_dw = vMax->win[3] - vMin->win[3];
+         const GLfloat eBot_dw = vMid->win[3] - vMin->win[3];
+         span.dwdx = oneOverArea * (eMaj_dw * eBot.dy - eMaj.dy * eBot_dw);
+         span.dwdy = oneOverArea * (eMaj.dx * eBot_dw - eMaj_dw * eBot.dx);
       }
+#endif
+#ifdef INTERP_FOG
+      span.interpMask |= SPAN_FOG;
       {
-         GLfloat eMaj_db, eBot_db;
-         eMaj_db = (GLint) vMax->color[2]
-                 - (GLint) vMin->color[2];
-         eBot_db = (GLint) vMid->color[2]
-                 - (GLint) vMin->color[2];
-         dbdx = oneOverArea * (eMaj_db * eBot.dy - eMaj.dy * eBot_db);
-         fdbdx = SignedFloatToFixed(dbdx);
-        dbdy = oneOverArea * (eMaj.dx * eBot_db - eMaj_db * eBot.dx);
+         const GLfloat eMaj_dfog = vMax->fog - vMin->fog;
+         const GLfloat eBot_dfog = vMid->fog - vMin->fog;
+         span.dfogdx = oneOverArea * (eMaj_dfog * eBot.dy - eMaj.dy * eBot_dfog);
+         span.dfogdy = oneOverArea * (eMaj.dx * eBot_dfog - eMaj_dfog * eBot.dx);
+         span.fogStep = span.dfogdx;
       }
 #endif
-#ifdef INTERP_SPEC
-      {
-         GLfloat eMaj_dsr, eBot_dsr;
-         eMaj_dsr = (GLint) vMax->specular[0]
-                  - (GLint) vMin->specular[0];
-         eBot_dsr = (GLint) vMid->specular[0]
-                  - (GLint) vMin->specular[0];
-         dsrdx = oneOverArea * (eMaj_dsr * eBot.dy - eMaj.dy * eBot_dsr);
-         fdsrdx = SignedFloatToFixed(dsrdx);
-         dsrdy = oneOverArea * (eMaj.dx * eBot_dsr - eMaj_dsr * eBot.dx);
+#ifdef INTERP_RGB
+      span.interpMask |= SPAN_RGBA;
+      if (ctx->Light.ShadeModel == GL_SMOOTH) {
+         GLfloat eMaj_dr = (GLfloat) ((ColorTemp) vMax->color[RCOMP] - vMin->color[RCOMP]);
+         GLfloat eBot_dr = (GLfloat) ((ColorTemp) vMid->color[RCOMP] - vMin->color[RCOMP]);
+         GLfloat eMaj_dg = (GLfloat) ((ColorTemp) vMax->color[GCOMP] - vMin->color[GCOMP]);
+         GLfloat eBot_dg = (GLfloat) ((ColorTemp) vMid->color[GCOMP] - vMin->color[GCOMP]);
+         GLfloat eMaj_db = (GLfloat) ((ColorTemp) vMax->color[BCOMP] - vMin->color[BCOMP]);
+         GLfloat eBot_db = (GLfloat) ((ColorTemp) vMid->color[BCOMP] - vMin->color[BCOMP]);
+#  ifdef INTERP_ALPHA
+         GLfloat eMaj_da = (GLfloat) ((ColorTemp) vMax->color[ACOMP] - vMin->color[ACOMP]);
+         GLfloat eBot_da = (GLfloat) ((ColorTemp) vMid->color[ACOMP] - vMin->color[ACOMP]);
+#  endif
+         span.drdx = oneOverArea * (eMaj_dr * eBot.dy - eMaj.dy * eBot_dr);
+         span.drdy = oneOverArea * (eMaj.dx * eBot_dr - eMaj_dr * eBot.dx);
+         span.dgdx = oneOverArea * (eMaj_dg * eBot.dy - eMaj.dy * eBot_dg);
+         span.dgdy = oneOverArea * (eMaj.dx * eBot_dg - eMaj_dg * eBot.dx);
+         span.dbdx = oneOverArea * (eMaj_db * eBot.dy - eMaj.dy * eBot_db);
+         span.dbdy = oneOverArea * (eMaj.dx * eBot_db - eMaj_db * eBot.dx);
+#  if CHAN_TYPE == GL_FLOAT
+         span.redStep   = span.drdx;
+         span.greenStep = span.dgdx;
+         span.blueStep  = span.dbdx;
+#  else
+         span.redStep   = SignedFloatToFixed(span.drdx);
+         span.greenStep = SignedFloatToFixed(span.dgdx);
+         span.blueStep  = SignedFloatToFixed(span.dbdx);
+#  endif /* GL_FLOAT */
+#  ifdef INTERP_ALPHA
+         span.dadx = oneOverArea * (eMaj_da * eBot.dy - eMaj.dy * eBot_da);
+         span.dady = oneOverArea * (eMaj.dx * eBot_da - eMaj_da * eBot.dx);
+#    if CHAN_TYPE == GL_FLOAT
+         span.alphaStep = span.dadx;
+#    else
+         span.alphaStep = SignedFloatToFixed(span.dadx);
+#    endif /* GL_FLOAT */
+#  endif /* INTERP_ALPHA */
       }
-      {
-         GLfloat eMaj_dsg, eBot_dsg;
-         eMaj_dsg = (GLint) vMax->specular[1]
-                  - (GLint) vMin->specular[1];
-        eBot_dsg = (GLint) vMid->specular[1]
-                  - (GLint) vMin->specular[1];
-         dsgdx = oneOverArea * (eMaj_dsg * eBot.dy - eMaj.dy * eBot_dsg);
-         fdsgdx = SignedFloatToFixed(dsgdx);
-         dsgdy = oneOverArea * (eMaj.dx * eBot_dsg - eMaj_dsg * eBot.dx);
+      else {
+         ASSERT (ctx->Light.ShadeModel == GL_FLAT);
+         span.interpMask |= SPAN_FLAT;
+         span.drdx = span.drdy = span.redStep   = 0;
+         span.dgdx = span.dgdy = span.greenStep = 0;
+         span.dbdx = span.dbdy = span.blueStep  = 0;
+#  ifdef INTERP_ALPHA
+         span.dadx = span.dady = span.alphaStep = 0;
+#  endif
       }
-      {
-         GLfloat eMaj_dsb, eBot_dsb;
-         eMaj_dsb = (GLint) vMax->specular[2]
-                  - (GLint) vMin->specular[2];
-         eBot_dsb = (GLint) vMid->specular[2]
-                  - (GLint) vMin->specular[2];
-         dsbdx = oneOverArea * (eMaj_dsb * eBot.dy - eMaj.dy * eBot_dsb);
-         fdsbdx = SignedFloatToFixed(dsbdx);
-        dsbdy = oneOverArea * (eMaj.dx * eBot_dsb - eMaj_dsb * eBot.dx);
+#endif /* INTERP_RGB */
+#ifdef INTERP_SPEC
+      span.interpMask |= SPAN_SPEC;
+      if (ctx->Light.ShadeModel == GL_SMOOTH) {
+         GLfloat eMaj_dsr = (GLfloat) ((ColorTemp) vMax->specular[RCOMP] - vMin->specular[RCOMP]);
+         GLfloat eBot_dsr = (GLfloat) ((ColorTemp) vMid->specular[RCOMP] - vMin->specular[RCOMP]);
+         GLfloat eMaj_dsg = (GLfloat) ((ColorTemp) vMax->specular[GCOMP] - vMin->specular[GCOMP]);
+         GLfloat eBot_dsg = (GLfloat) ((ColorTemp) vMid->specular[GCOMP] - vMin->specular[GCOMP]);
+         GLfloat eMaj_dsb = (GLfloat) ((ColorTemp) vMax->specular[BCOMP] - vMin->specular[BCOMP]);
+         GLfloat eBot_dsb = (GLfloat) ((ColorTemp) vMid->specular[BCOMP] - vMin->specular[BCOMP]);
+         span.dsrdx = oneOverArea * (eMaj_dsr * eBot.dy - eMaj.dy * eBot_dsr);
+         span.dsrdy = oneOverArea * (eMaj.dx * eBot_dsr - eMaj_dsr * eBot.dx);
+         span.dsgdx = oneOverArea * (eMaj_dsg * eBot.dy - eMaj.dy * eBot_dsg);
+         span.dsgdy = oneOverArea * (eMaj.dx * eBot_dsg - eMaj_dsg * eBot.dx);
+         span.dsbdx = oneOverArea * (eMaj_dsb * eBot.dy - eMaj.dy * eBot_dsb);
+         span.dsbdy = oneOverArea * (eMaj.dx * eBot_dsb - eMaj_dsb * eBot.dx);
+#  if CHAN_TYPE == GL_FLOAT
+         span.specRedStep   = span.dsrdx;
+         span.specGreenStep = span.dsgdx;
+         span.specBlueStep  = span.dsbdx;
+#  else
+         span.specRedStep   = SignedFloatToFixed(span.dsrdx);
+         span.specGreenStep = SignedFloatToFixed(span.dsgdx);
+         span.specBlueStep  = SignedFloatToFixed(span.dsbdx);
+#  endif
       }
-#endif
-#ifdef INTERP_ALPHA
-      {
-         GLfloat eMaj_da, eBot_da;
-         eMaj_da = (GLint) vMax->color[3]
-                 - (GLint) vMin->color[3];
-         eBot_da = (GLint) vMid->color[3]
-                 - (GLint) vMin->color[3];
-         dadx = oneOverArea * (eMaj_da * eBot.dy - eMaj.dy * eBot_da);
-         fdadx = SignedFloatToFixed(dadx);
-         dady = oneOverArea * (eMaj.dx * eBot_da - eMaj_da * eBot.dx);
+      else {
+         span.dsrdx = span.dsrdy = span.specRedStep   = 0;
+         span.dsgdx = span.dsgdy = span.specGreenStep = 0;
+         span.dsbdx = span.dsbdy = span.specBlueStep  = 0;
       }
-#endif
+#endif /* INTERP_SPEC */
 #ifdef INTERP_INDEX
-      {
-         GLfloat eMaj_di, eBot_di;
-         eMaj_di = (GLint) vMax->index
-                 - (GLint) vMin->index;
-         eBot_di = (GLint) vMid->index
-                 - (GLint) vMin->index;
+      span.interpMask |= SPAN_INDEX;
+      if (ctx->Light.ShadeModel == GL_SMOOTH) {
+         GLfloat eMaj_di = (GLfloat) ((GLint) vMax->index - (GLint) vMin->index);
+         GLfloat eBot_di = (GLfloat) ((GLint) vMid->index - (GLint) vMin->index);
          didx = oneOverArea * (eMaj_di * eBot.dy - eMaj.dy * eBot_di);
-         fdidx = SignedFloatToFixed(didx);
          didy = oneOverArea * (eMaj.dx * eBot_di - eMaj_di * eBot.dx);
+         span.indexStep = SignedFloatToFixed(didx);
+      }
+      else {
+         span.interpMask |= SPAN_FLAT;
+         didx = didy = 0.0F;
+         span.indexStep = 0;
       }
 #endif
 #ifdef INTERP_INT_TEX
+      span.interpMask |= SPAN_INT_TEXTURE;
       {
-         GLfloat eMaj_ds, eBot_ds;
-         eMaj_ds = (vMax->texcoord[0][0] - vMin->texcoord[0][0]) * S_SCALE;
-         eBot_ds = (vMid->texcoord[0][0] - vMin->texcoord[0][0]) * S_SCALE;
-         dsdx = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds);
-         fdsdx = SignedFloatToFixed(dsdx);
-         dsdy = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx);
-      }
-      {
-         GLfloat eMaj_dt, eBot_dt;
-         eMaj_dt = (vMax->texcoord[0][1] - vMin->texcoord[0][1]) * T_SCALE;
-         eBot_dt = (vMid->texcoord[0][1] - vMin->texcoord[0][1]) * T_SCALE;
-         dtdx = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt);
-         fdtdx = SignedFloatToFixed(dtdx);
-         dtdy = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx);
+         GLfloat eMaj_ds = (vMax->texcoord[0][0] - vMin->texcoord[0][0]) * S_SCALE;
+         GLfloat eBot_ds = (vMid->texcoord[0][0] - vMin->texcoord[0][0]) * S_SCALE;
+         GLfloat eMaj_dt = (vMax->texcoord[0][1] - vMin->texcoord[0][1]) * T_SCALE;
+         GLfloat eBot_dt = (vMid->texcoord[0][1] - vMin->texcoord[0][1]) * T_SCALE;
+         span.texStepX[0][0] = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds);
+         span.texStepY[0][0] = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx);
+         span.texStepX[0][1] = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt);
+         span.texStepY[0][1] = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx);
+         span.intTexStep[0] = SignedFloatToFixed(span.texStepX[0][0]);
+         span.intTexStep[1] = SignedFloatToFixed(span.texStepX[0][1]);
       }
-
 #endif
 #ifdef INTERP_TEX
+      span.interpMask |= SPAN_TEXTURE;
       {
-         GLfloat wMax = vMax->win[3];
-         GLfloat wMin = vMin->win[3];
-         GLfloat wMid = vMid->win[3];
-         GLfloat eMaj_ds, eBot_ds;
-         GLfloat eMaj_dt, eBot_dt;
-         GLfloat eMaj_du, eBot_du;
-         GLfloat eMaj_dv, eBot_dv;
-
-         eMaj_ds = vMax->texcoord[0][0] * wMax - vMin->texcoord[0][0] * wMin;
-         eBot_ds = vMid->texcoord[0][0] * wMid - vMin->texcoord[0][0] * wMin;
-         dsdx = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds);
-         dsdy = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx);
-
-        eMaj_dt = vMax->texcoord[0][1] * wMax - vMin->texcoord[0][1] * wMin;
-        eBot_dt = vMid->texcoord[0][1] * wMid - vMin->texcoord[0][1] * wMin;
-        dtdx = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt);
-        dtdy = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx);
-        
-        eMaj_du = vMax->texcoord[0][2] * wMax - vMin->texcoord[0][2] * wMin;
-        eBot_du = vMid->texcoord[0][2] * wMid - vMin->texcoord[0][2] * wMin;
-        dudx = oneOverArea * (eMaj_du * eBot.dy - eMaj.dy * eBot_du);
-        dudy = oneOverArea * (eMaj.dx * eBot_du - eMaj_du * eBot.dx);
-
-
-        eMaj_dv = vMax->texcoord[0][3] * wMax - vMin->texcoord[0][3] * wMin;
-        eBot_dv = vMid->texcoord[0][3] * wMid - vMin->texcoord[0][3] * wMin;
-        dvdx = oneOverArea * (eMaj_dv * eBot.dy - eMaj.dy * eBot_dv);
-        dvdy = oneOverArea * (eMaj.dx * eBot_dv - eMaj_dv * eBot.dx);
-      }
-#endif
-#ifdef INTERP_MULTITEX
-      {
-         GLfloat wMax = vMax->win[3];
-         GLfloat wMin = vMin->win[3];
-         GLfloat wMid = vMid->win[3];
-         GLuint u;
-         for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
-            if (ctx->Texture.Unit[u]._ReallyEnabled) {
-               GLfloat eMaj_ds, eBot_ds;
-               GLfloat eMaj_dt, eBot_dt;
-               GLfloat eMaj_du, eBot_du;
-               GLfloat eMaj_dv, eBot_dv;
-               eMaj_ds = vMax->texcoord[u][0] * wMax
-                       - vMin->texcoord[u][0] * wMin;
-               eBot_ds = vMid->texcoord[u][0] * wMid
-                       - vMin->texcoord[u][0] * wMin;
-               dsdx[u] = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds);
-               dsdy[u] = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx);
-
-              eMaj_dt = vMax->texcoord[u][1] * wMax
-                      - vMin->texcoord[u][1] * wMin;
-              eBot_dt = vMid->texcoord[u][1] * wMid
-                      - vMin->texcoord[u][1] * wMin;
-              dtdx[u] = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt);
-              dtdy[u] = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx);
-              
-              eMaj_du = vMax->texcoord[u][2] * wMax
-                       - vMin->texcoord[u][2] * wMin;
-              eBot_du = vMid->texcoord[u][2] * wMid
-                       - vMin->texcoord[u][2] * wMin;
-              dudx[u] = oneOverArea * (eMaj_du * eBot.dy - eMaj.dy * eBot_du);
-              dudy[u] = oneOverArea * (eMaj.dx * eBot_du - eMaj_du * eBot.dx);
-              
-              eMaj_dv = vMax->texcoord[u][3] * wMax
-                       - vMin->texcoord[u][3] * wMin;
-              eBot_dv = vMid->texcoord[u][3] * wMid
-                       - vMin->texcoord[u][3] * wMin;
-              dvdx[u] = oneOverArea * (eMaj_dv * eBot.dy - eMaj.dy * eBot_dv);
-              dvdy[u] = oneOverArea * (eMaj.dx * eBot_dv - eMaj_dv * eBot.dx);
-            }
-         }
+         /* win[3] is 1/W */
+         const GLfloat wMax = vMax->win[3], wMin = vMin->win[3], wMid = vMid->win[3];
+         TEX_UNIT_LOOP(
+            GLfloat eMaj_ds = vMax->texcoord[u][0] * wMax - vMin->texcoord[u][0] * wMin;
+            GLfloat eBot_ds = vMid->texcoord[u][0] * wMid - vMin->texcoord[u][0] * wMin;
+            GLfloat eMaj_dt = vMax->texcoord[u][1] * wMax - vMin->texcoord[u][1] * wMin;
+            GLfloat eBot_dt = vMid->texcoord[u][1] * wMid - vMin->texcoord[u][1] * wMin;
+            GLfloat eMaj_du = vMax->texcoord[u][2] * wMax - vMin->texcoord[u][2] * wMin;
+            GLfloat eBot_du = vMid->texcoord[u][2] * wMid - vMin->texcoord[u][2] * wMin;
+            GLfloat eMaj_dv = vMax->texcoord[u][3] * wMax - vMin->texcoord[u][3] * wMin;
+            GLfloat eBot_dv = vMid->texcoord[u][3] * wMid - vMin->texcoord[u][3] * wMin;
+            span.texStepX[u][0] = oneOverArea * (eMaj_ds * eBot.dy - eMaj.dy * eBot_ds);
+            span.texStepY[u][0] = oneOverArea * (eMaj.dx * eBot_ds - eMaj_ds * eBot.dx);
+            span.texStepX[u][1] = oneOverArea * (eMaj_dt * eBot.dy - eMaj.dy * eBot_dt);
+            span.texStepY[u][1] = oneOverArea * (eMaj.dx * eBot_dt - eMaj_dt * eBot.dx);
+            span.texStepX[u][2] = oneOverArea * (eMaj_du * eBot.dy - eMaj.dy * eBot_du);
+            span.texStepY[u][2] = oneOverArea * (eMaj.dx * eBot_du - eMaj_du * eBot.dx);
+            span.texStepX[u][3] = oneOverArea * (eMaj_dv * eBot.dy - eMaj.dy * eBot_dv);
+            span.texStepY[u][3] = oneOverArea * (eMaj.dx * eBot_dv - eMaj_dv * eBot.dx);
+         )
       }
 #endif
 
        * inside the triangle.
        *
        * Next we creep down the major edge until we reach that y,
-       * and compute the corresponding x coordinate on the edge. 
+       * and compute the corresponding x coordinate on the edge.
        * Then we find the half-integral x that lies on or just
        * inside the edge.  This is the first pixel that might lie in
        * the interior of the triangle.  (We won't know for sure
 
       {
          int subTriangle;
-         GLfixed fx, fxLeftEdge, fxRightEdge, fdxLeftEdge, fdxRightEdge;
+         GLfixed fx;
+         GLfixed fxLeftEdge = 0, fxRightEdge = 0;
+         GLfixed fdxLeftEdge = 0, fdxRightEdge = 0;
          GLfixed fdxOuter;
          int idxOuter;
          float dxOuter;
-         GLfixed fError, fdError;
+         GLfixed fError = 0, fdError = 0;
          float adjx, adjy;
          GLfixed fy;
-         int iy;
 #ifdef PIXEL_ADDRESS
-         PIXEL_TYPE *pRow;
-         int dPRowOuter, dPRowInner;  /* offset in bytes */
+         PIXEL_TYPE *pRow = NULL;
+         int dPRowOuter = 0, dPRowInner;  /* offset in bytes */
 #endif
 #ifdef INTERP_Z
 #  ifdef DEPTH_TYPE
-         DEPTH_TYPE *zRow;
-         int dZRowOuter, dZRowInner;  /* offset in bytes */
+         DEPTH_TYPE *zRow = NULL;
+         int dZRowOuter = 0, dZRowInner;  /* offset in bytes */
 #  endif
-         GLfixed fz, fdzOuter, fdzInner;
-         GLfixed ffog, fdfogOuter, fdfogInner;
+         GLfixed zLeft = 0, fdzOuter = 0, fdzInner;
 #endif
-#ifdef INTERP_RGB
-         GLfixed fr, fdrOuter, fdrInner;
-         GLfixed fg, fdgOuter, fdgInner;
-         GLfixed fb, fdbOuter, fdbInner;
+#ifdef INTERP_W
+         GLfloat wLeft, dwOuter, dwInner;
 #endif
-#ifdef INTERP_SPEC
-         GLfixed fsr, fdsrOuter, fdsrInner;
-         GLfixed fsg, fdsgOuter, fdsgInner;
-         GLfixed fsb, fdsbOuter, fdsbInner;
+#ifdef INTERP_FOG
+         GLfloat fogLeft = 0, dfogOuter = 0, dfogInner;
+#endif
+#ifdef INTERP_RGB
+         ColorTemp rLeft = 0, fdrOuter = 0, fdrInner;
+         ColorTemp gLeft = 0, fdgOuter = 0, fdgInner;
+         ColorTemp bLeft = 0, fdbOuter = 0, fdbInner;
 #endif
 #ifdef INTERP_ALPHA
-         GLfixed fa, fdaOuter, fdaInner;
+         ColorTemp aLeft = 0, fdaOuter = 0, fdaInner;
+#endif
+#ifdef INTERP_SPEC
+         ColorTemp srLeft=0, dsrOuter=0, dsrInner;
+         ColorTemp sgLeft=0, dsgOuter=0, dsgInner;
+         ColorTemp sbLeft=0, dsbOuter=0, dsbInner;
 #endif
 #ifdef INTERP_INDEX
-         GLfixed fi, fdiOuter, fdiInner;
+         GLfixed iLeft=0, diOuter=0, diInner;
 #endif
 #ifdef INTERP_INT_TEX
-         GLfixed fs, fdsOuter, fdsInner;
-         GLfixed ft, fdtOuter, fdtInner;
+         GLfixed sLeft=0, dsOuter=0, dsInner;
+         GLfixed tLeft=0, dtOuter=0, dtInner;
 #endif
 #ifdef INTERP_TEX
-         GLfloat sLeft, dsOuter, dsInner;
-         GLfloat tLeft, dtOuter, dtInner;
-         GLfloat uLeft, duOuter, duInner;
-         GLfloat vLeft, dvOuter, dvInner;
-#endif
-#ifdef INTERP_MULTITEX
-         GLfloat sLeft[MAX_TEXTURE_UNITS];
-         GLfloat tLeft[MAX_TEXTURE_UNITS];
-         GLfloat uLeft[MAX_TEXTURE_UNITS];
-         GLfloat vLeft[MAX_TEXTURE_UNITS];
-         GLfloat dsOuter[MAX_TEXTURE_UNITS], dsInner[MAX_TEXTURE_UNITS];
-         GLfloat dtOuter[MAX_TEXTURE_UNITS], dtInner[MAX_TEXTURE_UNITS];
-         GLfloat duOuter[MAX_TEXTURE_UNITS], duInner[MAX_TEXTURE_UNITS];
-         GLfloat dvOuter[MAX_TEXTURE_UNITS], dvInner[MAX_TEXTURE_UNITS];
+         GLfloat sLeft[MAX_TEXTURE_COORD_UNITS];
+         GLfloat tLeft[MAX_TEXTURE_COORD_UNITS];
+         GLfloat uLeft[MAX_TEXTURE_COORD_UNITS];
+         GLfloat vLeft[MAX_TEXTURE_COORD_UNITS];
+         GLfloat dsOuter[MAX_TEXTURE_COORD_UNITS], dsInner[MAX_TEXTURE_COORD_UNITS];
+         GLfloat dtOuter[MAX_TEXTURE_COORD_UNITS], dtInner[MAX_TEXTURE_COORD_UNITS];
+         GLfloat duOuter[MAX_TEXTURE_COORD_UNITS], duInner[MAX_TEXTURE_COORD_UNITS];
+         GLfloat dvOuter[MAX_TEXTURE_COORD_UNITS], dvInner[MAX_TEXTURE_COORD_UNITS];
 #endif
 
          for (subTriangle=0; subTriangle<=1; subTriangle++) {
 
             if (subTriangle==0) {
                /* bottom half */
-               if (ltor) {
+               if (scan_from_left_to_right) {
                   eLeft = &eMaj;
                   eRight = &eBot;
                   lines = eRight->lines;
             }
             else {
                /* top half */
-               if (ltor) {
+               if (scan_from_left_to_right) {
                   eLeft = &eMaj;
                   eRight = &eTop;
                   lines = eRight->lines;
                (void) dxOuter;
 
                fy = eLeft->fsy;
-               iy = FixedToInt(fy);
+               span.y = FixedToInt(fy);
 
                adjx = (float)(fx - eLeft->fx0);  /* SCALED! */
                adjy = eLeft->adjy;              /* SCALED! */
+#ifndef __IBMCPP__
                (void) adjx;  /* silence compiler warnings */
                (void) adjy;  /* silence compiler warnings */
-
+#endif
                vLower = eLeft->v0;
+#ifndef __IBMCPP__
                (void) vLower;  /* silence compiler warnings */
+#endif
 
 #ifdef PIXEL_ADDRESS
                {
-                  pRow = PIXEL_ADDRESS( FixedToInt(fxLeftEdge), iy );
+                  pRow = (PIXEL_TYPE *) PIXEL_ADDRESS(FixedToInt(fxLeftEdge), span.y);
                   dPRowOuter = -((int)BYTES_PER_ROW) + idxOuter * sizeof(PIXEL_TYPE);
                   /* negative because Y=0 at bottom and increases upward */
                }
                   GLfloat z0 = vLower->win[2];
                   if (depthBits <= 16) {
                      /* interpolate fixed-pt values */
-                     GLfloat tmp = (z0 * FIXED_SCALE +
-                                    dzdx * adjx + dzdy * adjy) + FIXED_HALF;
+                     GLfloat tmp = (z0 * FIXED_SCALE + span.dzdx * adjx + span.dzdy * adjy) + FIXED_HALF;
                      if (tmp < MAX_GLUINT / 2)
-                        fz = (GLfixed) tmp;
+                        zLeft = (GLfixed) tmp;
                      else
-                        fz = MAX_GLUINT / 2;
-                     fdzOuter = SignedFloatToFixed(dzdy + dxOuter * dzdx);
+                        zLeft = MAX_GLUINT / 2;
+                     fdzOuter = SignedFloatToFixed(span.dzdy + dxOuter * span.dzdx);
                   }
                   else {
                      /* interpolate depth values exactly */
-                     fz = (GLint) (z0 + dzdx*FixedToFloat(adjx) + dzdy*FixedToFloat(adjy));
-                     fdzOuter = (GLint) (dzdy + dxOuter * dzdx);
+                     zLeft = (GLint) (z0 + span.dzdx * FixedToFloat(adjx) + span.dzdy * FixedToFloat(adjy));
+                     fdzOuter = (GLint) (span.dzdy + dxOuter * span.dzdx);
                   }
 #  ifdef DEPTH_TYPE
-                  zRow = (DEPTH_TYPE *) _mesa_zbuffer_address(ctx, FixedToInt(fxLeftEdge), iy);
+                  zRow = (DEPTH_TYPE *)
+                    _swrast_zbuffer_address(ctx, FixedToInt(fxLeftEdge), span.y);
                   dZRowOuter = (ctx->DrawBuffer->Width + idxOuter) * sizeof(DEPTH_TYPE);
 #  endif
                }
-              {
-                 ffog = FloatToFixed(vLower->fog) * 256 + dfogdx * adjx + dfogdy * adjy + FIXED_HALF;
-                 fdfogOuter = SignedFloatToFixed(dfogdy + dxOuter * dfogdx);
-              }
+#endif
+#ifdef INTERP_W
+               wLeft = vLower->win[3] + (span.dwdx * adjx + span.dwdy * adjy) * (1.0F/FIXED_SCALE);
+               dwOuter = span.dwdy + dxOuter * span.dwdx;
+#endif
+#ifdef INTERP_FOG
+               fogLeft = vLower->fog + (span.dfogdx * adjx + span.dfogdy * adjy) * (1.0F/FIXED_SCALE);
+               dfogOuter = span.dfogdy + dxOuter * span.dfogdx;
 #endif
 #ifdef INTERP_RGB
-               fr = (GLfixed)(IntToFixed(vLower->color[0])
-                              + drdx * adjx + drdy * adjy) + FIXED_HALF;
-               fdrOuter = SignedFloatToFixed(drdy + dxOuter * drdx);
-
-               fg = (GLfixed)(IntToFixed(vLower->color[1])
-                              + dgdx * adjx + dgdy * adjy) + FIXED_HALF;
-               fdgOuter = SignedFloatToFixed(dgdy + dxOuter * dgdx);
-
-               fb = (GLfixed)(IntToFixed(vLower->color[2])
-                              + dbdx * adjx + dbdy * adjy) + FIXED_HALF;
-               fdbOuter = SignedFloatToFixed(dbdy + dxOuter * dbdx);
+               if (ctx->Light.ShadeModel == GL_SMOOTH) {
+#  if CHAN_TYPE == GL_FLOAT
+                  rLeft = vLower->color[RCOMP] + (span.drdx * adjx + span.drdy * adjy) * (1.0F / FIXED_SCALE);
+                  gLeft = vLower->color[GCOMP] + (span.dgdx * adjx + span.dgdy * adjy) * (1.0F / FIXED_SCALE);
+                  bLeft = vLower->color[BCOMP] + (span.dbdx * adjx + span.dbdy * adjy) * (1.0F / FIXED_SCALE);
+                  fdrOuter = span.drdy + dxOuter * span.drdx;
+                  fdgOuter = span.dgdy + dxOuter * span.dgdx;
+                  fdbOuter = span.dbdy + dxOuter * span.dbdx;
+#  else
+                  rLeft = (ChanToFixed(vLower->color[RCOMP]) + span.drdx * adjx + span.drdy * adjy) + FIXED_HALF;
+                  gLeft = (ChanToFixed(vLower->color[GCOMP]) + span.dgdx * adjx + span.dgdy * adjy) + FIXED_HALF;
+                  bLeft = (ChanToFixed(vLower->color[BCOMP]) + span.dbdx * adjx + span.dbdy * adjy) + FIXED_HALF;
+                  fdrOuter = SignedFloatToFixed(span.drdy + dxOuter * span.drdx);
+                  fdgOuter = SignedFloatToFixed(span.dgdy + dxOuter * span.dgdx);
+                  fdbOuter = SignedFloatToFixed(span.dbdy + dxOuter * span.dbdx);
+#  endif
+#  ifdef INTERP_ALPHA
+#    if CHAN_TYPE == GL_FLOAT
+                  aLeft = vLower->color[ACOMP] + (span.dadx * adjx + span.dady * adjy) * (1.0F / FIXED_SCALE);
+                  fdaOuter = span.dady + dxOuter * span.dadx;
+#    else
+                  aLeft = (ChanToFixed(vLower->color[ACOMP]) + span.dadx * adjx + span.dady * adjy) + FIXED_HALF;
+                  fdaOuter = SignedFloatToFixed(span.dady + dxOuter * span.dadx);
+#    endif
+#  endif
+               }
+               else {
+                  ASSERT (ctx->Light.ShadeModel == GL_FLAT);
+#  if CHAN_TYPE == GL_FLOAT
+                  rLeft = v2->color[RCOMP];
+                  gLeft = v2->color[GCOMP];
+                  bLeft = v2->color[BCOMP];
+                  fdrOuter = fdgOuter = fdbOuter = 0.0F;
+#  else
+                  rLeft = ChanToFixed(v2->color[RCOMP]);
+                  gLeft = ChanToFixed(v2->color[GCOMP]);
+                  bLeft = ChanToFixed(v2->color[BCOMP]);
+                  fdrOuter = fdgOuter = fdbOuter = 0;
+#  endif
+#  ifdef INTERP_ALPHA
+#    if CHAN_TYPE == GL_FLOAT
+                  aLeft = v2->color[ACOMP];
+                  fdaOuter = 0.0F;
+#    else
+                  aLeft = ChanToFixed(v2->color[ACOMP]);
+                  fdaOuter = 0;
+#    endif
+#  endif
+               }
 #endif
-#ifdef INTERP_SPEC
-               fsr = (GLfixed)(IntToFixed(vLower->specular[0])
-                               + dsrdx * adjx + dsrdy * adjy) + FIXED_HALF;
-               fdsrOuter = SignedFloatToFixed(dsrdy + dxOuter * dsrdx);
-
-               fsg = (GLfixed)(IntToFixed(vLower->specular[1])
-                               + dsgdx * adjx + dsgdy * adjy) + FIXED_HALF;
-               fdsgOuter = SignedFloatToFixed(dsgdy + dxOuter * dsgdx);
 
-               fsb = (GLfixed)(IntToFixed(vLower->specular[2])
-                               + dsbdx * adjx + dsbdy * adjy) + FIXED_HALF;
-               fdsbOuter = SignedFloatToFixed(dsbdy + dxOuter * dsbdx);
-#endif
-#ifdef INTERP_ALPHA
-               fa = (GLfixed)(IntToFixed(vLower->color[3])
-                              + dadx * adjx + dady * adjy) + FIXED_HALF;
-               fdaOuter = SignedFloatToFixed(dady + dxOuter * dadx);
+#ifdef INTERP_SPEC
+               if (ctx->Light.ShadeModel == GL_SMOOTH) {
+#  if CHAN_TYPE == GL_FLOAT
+                  srLeft = vLower->specular[RCOMP] + (span.dsrdx * adjx + span.dsrdy * adjy) * (1.0F / FIXED_SCALE);
+                  sgLeft = vLower->specular[GCOMP] + (span.dsgdx * adjx + span.dsgdy * adjy) * (1.0F / FIXED_SCALE);
+                  sbLeft = vLower->specular[BCOMP] + (span.dsbdx * adjx + span.dsbdy * adjy) * (1.0F / FIXED_SCALE);
+                  dsrOuter = span.dsrdy + dxOuter * span.dsrdx;
+                  dsgOuter = span.dsgdy + dxOuter * span.dsgdx;
+                  dsbOuter = span.dsbdy + dxOuter * span.dsbdx;
+#  else
+                  srLeft = (GLfixed) (ChanToFixed(vLower->specular[RCOMP]) + span.dsrdx * adjx + span.dsrdy * adjy) + FIXED_HALF;
+                  sgLeft = (GLfixed) (ChanToFixed(vLower->specular[GCOMP]) + span.dsgdx * adjx + span.dsgdy * adjy) + FIXED_HALF;
+                  sbLeft = (GLfixed) (ChanToFixed(vLower->specular[BCOMP]) + span.dsbdx * adjx + span.dsbdy * adjy) + FIXED_HALF;
+                  dsrOuter = SignedFloatToFixed(span.dsrdy + dxOuter * span.dsrdx);
+                  dsgOuter = SignedFloatToFixed(span.dsgdy + dxOuter * span.dsgdx);
+                  dsbOuter = SignedFloatToFixed(span.dsbdy + dxOuter * span.dsbdx);
+#  endif
+               }
+               else {
+#if  CHAN_TYPE == GL_FLOAT
+                  srLeft = v2->specular[RCOMP];
+                  sgLeft = v2->specular[GCOMP];
+                  sbLeft = v2->specular[BCOMP];
+                  dsrOuter = dsgOuter = dsbOuter = 0.0F;
+#  else
+                  srLeft = ChanToFixed(v2->specular[RCOMP]);
+                  sgLeft = ChanToFixed(v2->specular[GCOMP]);
+                  sbLeft = ChanToFixed(v2->specular[BCOMP]);
+                  dsrOuter = dsgOuter = dsbOuter = 0;
+#  endif
+               }
 #endif
+
 #ifdef INTERP_INDEX
-               fi = (GLfixed)(vLower->index * FIXED_SCALE
-                              + didx * adjx + didy * adjy) + FIXED_HALF;
-               fdiOuter = SignedFloatToFixed(didy + dxOuter * didx);
+               if (ctx->Light.ShadeModel == GL_SMOOTH) {
+                  iLeft = (GLfixed)(vLower->index * FIXED_SCALE
+                                 + didx * adjx + didy * adjy) + FIXED_HALF;
+                  diOuter = SignedFloatToFixed(didy + dxOuter * didx);
+               }
+               else {
+                  iLeft = (GLfixed) (v2->index * FIXED_SCALE);
+                  diOuter = 0;
+               }
 #endif
 #ifdef INTERP_INT_TEX
                {
                   GLfloat s0, t0;
                   s0 = vLower->texcoord[0][0] * S_SCALE;
-                  fs = (GLfixed)(s0 * FIXED_SCALE + dsdx * adjx + dsdy * adjy) + FIXED_HALF;
-                  fdsOuter = SignedFloatToFixed(dsdy + dxOuter * dsdx);
-
-                 t0 = vLower->texcoord[0][1] * T_SCALE;
-                 ft = (GLfixed)(t0 * FIXED_SCALE + dtdx * adjx + dtdy * adjy) + FIXED_HALF;
-                 fdtOuter = SignedFloatToFixed(dtdy + dxOuter * dtdx);
-              }
-#endif
-#ifdef INTERP_TEX
-               {
-                  GLfloat invW = vLower->win[3];
-                  GLfloat s0, t0, u0, v0;
-                  s0 = vLower->texcoord[0][0] * invW;
-                  sLeft = s0 + (dsdx * adjx + dsdy * adjy) * (1.0F/FIXED_SCALE);
-                  dsOuter = dsdy + dxOuter * dsdx;
-                 t0 = vLower->texcoord[0][1] * invW;
-                 tLeft = t0 + (dtdx * adjx + dtdy * adjy) * (1.0F/FIXED_SCALE);
-                 dtOuter = dtdy + dxOuter * dtdx;
-                 u0 = vLower->texcoord[0][2] * invW;
-                 uLeft = u0 + (dudx * adjx + dudy * adjy) * (1.0F/FIXED_SCALE);
-                 duOuter = dudy + dxOuter * dudx;
-                 v0 = vLower->texcoord[0][3] * invW;
-                 vLeft = v0 + (dvdx * adjx + dvdy * adjy) * (1.0F/FIXED_SCALE);
-                 dvOuter = dvdy + dxOuter * dvdx;
+                  sLeft = (GLfixed)(s0 * FIXED_SCALE + span.texStepX[0][0] * adjx
+                                 + span.texStepY[0][0] * adjy) + FIXED_HALF;
+                  dsOuter = SignedFloatToFixed(span.texStepY[0][0] + dxOuter * span.texStepX[0][0]);
+
+                  t0 = vLower->texcoord[0][1] * T_SCALE;
+                  tLeft = (GLfixed)(t0 * FIXED_SCALE + span.texStepX[0][1] * adjx
+                                 + span.texStepY[0][1] * adjy) + FIXED_HALF;
+                  dtOuter = SignedFloatToFixed(span.texStepY[0][1] + dxOuter * span.texStepX[0][1]);
                }
 #endif
-#ifdef INTERP_MULTITEX
-               {
-                  GLuint u;
-                  for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
-                     if (ctx->Texture.Unit[u]._ReallyEnabled) {
-                        GLfloat invW = vLower->win[3];
-                        GLfloat s0, t0, u0, v0;
-                        s0 = vLower->texcoord[u][0] * invW;
-                        sLeft[u] = s0 + (dsdx[u] * adjx + dsdy[u] * adjy) * (1.0F/FIXED_SCALE);
-                        dsOuter[u] = dsdy[u] + dxOuter * dsdx[u];
-                       t0 = vLower->texcoord[u][1] * invW;
-                       tLeft[u] = t0 + (dtdx[u] * adjx + dtdy[u] * adjy) * (1.0F/FIXED_SCALE);
-                       dtOuter[u] = dtdy[u] + dxOuter * dtdx[u];
-                       u0 = vLower->texcoord[u][2] * invW;
-                       uLeft[u] = u0 + (dudx[u] * adjx + dudy[u] * adjy) * (1.0F/FIXED_SCALE);
-                       duOuter[u] = dudy[u] + dxOuter * dudx[u];
-                       v0 = vLower->texcoord[u][3] * invW;
-                        vLeft[u] = v0 + (dvdx[u] * adjx + dvdy[u] * adjy) * (1.0F/FIXED_SCALE);
-                        dvOuter[u] = dvdy[u] + dxOuter * dvdx[u];
-                     }
-                  }
-               }
+#ifdef INTERP_TEX
+               TEX_UNIT_LOOP(
+                  const GLfloat invW = vLower->win[3];
+                  const GLfloat s0 = vLower->texcoord[u][0] * invW;
+                  const GLfloat t0 = vLower->texcoord[u][1] * invW;
+                  const GLfloat u0 = vLower->texcoord[u][2] * invW;
+                  const GLfloat v0 = vLower->texcoord[u][3] * invW;
+                  sLeft[u] = s0 + (span.texStepX[u][0] * adjx + span.texStepY[u][0] * adjy) * (1.0F/FIXED_SCALE);
+                  tLeft[u] = t0 + (span.texStepX[u][1] * adjx + span.texStepY[u][1] * adjy) * (1.0F/FIXED_SCALE);
+                  uLeft[u] = u0 + (span.texStepX[u][2] * adjx + span.texStepY[u][2] * adjy) * (1.0F/FIXED_SCALE);
+                  vLeft[u] = v0 + (span.texStepX[u][3] * adjx + span.texStepY[u][3] * adjy) * (1.0F/FIXED_SCALE);
+                  dsOuter[u] = span.texStepY[u][0] + dxOuter * span.texStepX[u][0];
+                  dtOuter[u] = span.texStepY[u][1] + dxOuter * span.texStepX[u][1];
+                  duOuter[u] = span.texStepY[u][2] + dxOuter * span.texStepX[u][2];
+                  dvOuter[u] = span.texStepY[u][3] + dxOuter * span.texStepX[u][3];
+               )
 #endif
-
             } /*if setupLeft*/
 
 
 #  ifdef DEPTH_TYPE
             dZRowInner = dZRowOuter + sizeof(DEPTH_TYPE);
 #  endif
-            fdzInner = fdzOuter + fdzdx;
-            fdfogInner = fdfogOuter + fdfogdx;
+            fdzInner = fdzOuter + span.zStep;
 #endif
-#ifdef INTERP_RGB
-            fdrInner = fdrOuter + fdrdx;
-            fdgInner = fdgOuter + fdgdx;
-            fdbInner = fdbOuter + fdbdx;
+#ifdef INTERP_W
+            dwInner = dwOuter + span.dwdx;
 #endif
-#ifdef INTERP_SPEC
-            fdsrInner = fdsrOuter + fdsrdx;
-            fdsgInner = fdsgOuter + fdsgdx;
-            fdsbInner = fdsbOuter + fdsbdx;
+#ifdef INTERP_FOG
+            dfogInner = dfogOuter + span.dfogdx;
 #endif
-#ifdef INTERP_ALPHA
-            fdaInner = fdaOuter + fdadx;
+#if defined(INTERP_RGB)
+            fdrInner = fdrOuter + span.redStep;
+            fdgInner = fdgOuter + span.greenStep;
+            fdbInner = fdbOuter + span.blueStep;
+#endif
+#if defined(INTERP_ALPHA)
+            fdaInner = fdaOuter + span.alphaStep;
+#endif
+#if defined(INTERP_SPEC)
+            dsrInner = dsrOuter + span.specRedStep;
+            dsgInner = dsgOuter + span.specGreenStep;
+            dsbInner = dsbOuter + span.specBlueStep;
 #endif
 #ifdef INTERP_INDEX
-            fdiInner = fdiOuter + fdidx;
+            diInner = diOuter + span.indexStep;
 #endif
 #ifdef INTERP_INT_TEX
-            fdsInner = fdsOuter + fdsdx;
-            fdtInner = fdtOuter + fdtdx;
+            dsInner = dsOuter + span.intTexStep[0];
+            dtInner = dtOuter + span.intTexStep[1];
 #endif
 #ifdef INTERP_TEX
-           dsInner = dsOuter + dsdx;
-           dtInner = dtOuter + dtdx;
-           duInner = duOuter + dudx;
-           dvInner = dvOuter + dvdx;
-#endif
-#ifdef INTERP_MULTITEX
-            {
-               GLuint u;
-               for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
-                  if (ctx->Texture.Unit[u]._ReallyEnabled) {
-                     dsInner[u] = dsOuter[u] + dsdx[u];
-                     dtInner[u] = dtOuter[u] + dtdx[u];
-                     duInner[u] = duOuter[u] + dudx[u];
-                     dvInner[u] = dvOuter[u] + dvdx[u];
-                  }
-               }
-            }
+            TEX_UNIT_LOOP(
+               dsInner[u] = dsOuter[u] + span.texStepX[u][0];
+               dtInner[u] = dtOuter[u] + span.texStepX[u][1];
+               duInner[u] = duOuter[u] + span.texStepX[u][2];
+               dvInner[u] = dvOuter[u] + span.texStepX[u][3];
+            )
 #endif
 
-            while (lines>0) {
+            while (lines > 0) {
                /* initialize the span interpolants to the leftmost value */
                /* ff = fixed-pt fragment */
-               GLint left = FixedToInt(fxLeftEdge);
-               GLint right = FixedToInt(fxRightEdge);
+               const GLint right = FixedToInt(fxRightEdge);
+
+               span.x = FixedToInt(fxLeftEdge);
+
+               if (right <= span.x)
+                  span.end = 0;
+               else
+                  span.end = right - span.x;
+
 #ifdef INTERP_Z
-               GLfixed ffz = fz;
-               GLfixed fffog = ffog;
+               span.z = zLeft;
 #endif
-#ifdef INTERP_RGB
-               GLfixed ffr = fr,  ffg = fg,  ffb = fb;
+#ifdef INTERP_W
+               span.w = wLeft;
 #endif
-#ifdef INTERP_SPEC
-               GLfixed ffsr = fsr,  ffsg = fsg,  ffsb = fsb;
+#ifdef INTERP_FOG
+               span.fog = fogLeft;
 #endif
-#ifdef INTERP_ALPHA
-               GLfixed ffa = fa;
+#if defined(INTERP_RGB)
+               span.red = rLeft;
+               span.green = gLeft;
+               span.blue = bLeft;
+#endif
+#if defined(INTERP_ALPHA)
+               span.alpha = aLeft;
+#endif
+#if defined(INTERP_SPEC)
+               span.specRed = srLeft;
+               span.specGreen = sgLeft;
+               span.specBlue = sbLeft;
 #endif
 #ifdef INTERP_INDEX
-               GLfixed ffi = fi;
+               span.index = iLeft;
 #endif
 #ifdef INTERP_INT_TEX
-               GLfixed ffs = fs,  fft = ft;
+               span.intTex[0] = sLeft;
+               span.intTex[1] = tLeft;
 #endif
+
 #ifdef INTERP_TEX
-               GLfloat ss = sLeft, tt = tLeft, uu = uLeft, vv = vLeft;
-#endif
-#ifdef INTERP_MULTITEX
-               GLfloat ss[MAX_TEXTURE_UNITS];
-               GLfloat tt[MAX_TEXTURE_UNITS];
-               GLfloat uu[MAX_TEXTURE_UNITS];
-               GLfloat vv[MAX_TEXTURE_UNITS];
-               {
-                  GLuint u;
-                  for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
-                     if (ctx->Texture.Unit[u]._ReallyEnabled) {
-                        ss[u] = sLeft[u];
-                        tt[u] = tLeft[u];
-                        uu[u] = uLeft[u];
-                        vv[u] = vLeft[u];
-                     }
-                  }
-               }
+               TEX_UNIT_LOOP(
+                  span.tex[u][0] = sLeft[u];
+                  span.tex[u][1] = tLeft[u];
+                  span.tex[u][2] = uLeft[u];
+                  span.tex[u][3] = vLeft[u];
+               )
 #endif
 
 #ifdef INTERP_RGB
                {
                   /* need this to accomodate round-off errors */
-                  GLfixed ffrend = ffr+(right-left-1)*fdrdx;
-                  GLfixed ffgend = ffg+(right-left-1)*fdgdx;
-                  GLfixed ffbend = ffb+(right-left-1)*fdbdx;
-                  if (ffrend<0) ffr -= ffrend;
-                  if (ffgend<0) ffg -= ffgend;
-                  if (ffbend<0) ffb -= ffbend;
-                  if (ffr<0) ffr = 0;
-                  if (ffg<0) ffg = 0;
-                  if (ffb<0) ffb = 0;
+                  const GLint len = right - span.x - 1;
+                  GLfixed ffrend = span.red + len * span.redStep;
+                  GLfixed ffgend = span.green + len * span.greenStep;
+                  GLfixed ffbend = span.blue + len * span.blueStep;
+                  if (ffrend < 0) {
+                     span.red -= ffrend;
+                     if (span.red < 0)
+                        span.red = 0;
+                  }
+                  if (ffgend < 0) {
+                     span.green -= ffgend;
+                     if (span.green < 0)
+                        span.green = 0;
+                  }
+                  if (ffbend < 0) {
+                     span.blue -= ffbend;
+                     if (span.blue < 0)
+                        span.blue = 0;
+                  }
                }
 #endif
-#ifdef INTERP_SPEC
+#ifdef INTERP_ALPHA
                {
-                  /* need this to accomodate round-off errors */
-                  GLfixed ffsrend = ffsr+(right-left-1)*fdsrdx;
-                  GLfixed ffsgend = ffsg+(right-left-1)*fdsgdx;
-                  GLfixed ffsbend = ffsb+(right-left-1)*fdsbdx;
-                  if (ffsrend<0) ffsr -= ffsrend;
-                  if (ffsgend<0) ffsg -= ffsgend;
-                  if (ffsbend<0) ffsb -= ffsbend;
-                  if (ffsr<0) ffsr = 0;
-                  if (ffsg<0) ffsg = 0;
-                  if (ffsb<0) ffsb = 0;
+                  const GLint len = right - span.x - 1;
+                  GLfixed ffaend = span.alpha + len * span.alphaStep;
+                  if (ffaend < 0) {
+                     span.alpha -= ffaend;
+                     if (span.alpha < 0)
+                        span.alpha = 0;
+                  }
                }
 #endif
-#ifdef INTERP_ALPHA
+#ifdef INTERP_SPEC
                {
-                  GLfixed ffaend = ffa+(right-left-1)*fdadx;
-                  if (ffaend<0) ffa -= ffaend;
-                  if (ffa<0) ffa = 0;
+                  /* need this to accomodate round-off errors */
+                  const GLint len = right - span.x - 1;
+                  GLfixed ffsrend = span.specRed + len * span.specRedStep;
+                  GLfixed ffsgend = span.specGreen + len * span.specGreenStep;
+                  GLfixed ffsbend = span.specBlue + len * span.specBlueStep;
+                  if (ffsrend < 0) {
+                     span.specRed -= ffsrend;
+                     if (span.specRed < 0)
+                        span.specRed = 0;
+                  }
+                  if (ffsgend < 0) {
+                     span.specGreen -= ffsgend;
+                     if (span.specGreen < 0)
+                        span.specGreen = 0;
+                  }
+                  if (ffsbend < 0) {
+                     span.specBlue -= ffsbend;
+                     if (span.specBlue < 0)
+                        span.specBlue = 0;
+                  }
                }
 #endif
 #ifdef INTERP_INDEX
-               if (ffi<0) ffi = 0;
+               if (span.index < 0)  span.index = 0;
 #endif
 
-               INNER_LOOP( left, right, iy );
+               /* This is where we actually generate fragments */
+               if (span.end > 0) {
+                  RENDER_SPAN( span );
+               }
 
                /*
                 * Advance to the next scan line.  Compute the
                 * pixel-center x coordinate so that it stays
                 * on or inside the major edge.
                 */
-               iy++;
+               (span.y)++;
                lines--;
 
                fxLeftEdge += fdxLeftEdge;
                if (fError >= 0) {
                   fError -= FIXED_ONE;
 #ifdef PIXEL_ADDRESS
-                  pRow = (PIXEL_TYPE *) ((GLubyte*)pRow + dPRowOuter);
+                  pRow = (PIXEL_TYPE *) ((GLubyte *) pRow + dPRowOuter);
 #endif
 #ifdef INTERP_Z
 #  ifdef DEPTH_TYPE
-                  zRow = (DEPTH_TYPE *) ((GLubyte*)zRow + dZRowOuter);
+                  zRow = (DEPTH_TYPE *) ((GLubyte *) zRow + dZRowOuter);
 #  endif
-                  fz += fdzOuter;
-                  ffog += fdfogOuter; 
+                  zLeft += fdzOuter;
 #endif
-#ifdef INTERP_RGB
-                  fr += fdrOuter;   fg += fdgOuter;   fb += fdbOuter;
+#ifdef INTERP_W
+                  wLeft += dwOuter;
 #endif
-#ifdef INTERP_SPEC
-                  fsr += fdsrOuter;   fsg += fdsgOuter;   fsb += fdsbOuter;
+#ifdef INTERP_FOG
+                  fogLeft += dfogOuter;
 #endif
-#ifdef INTERP_ALPHA
-                  fa += fdaOuter;
+#if defined(INTERP_RGB)
+                  rLeft += fdrOuter;
+                  gLeft += fdgOuter;
+                  bLeft += fdbOuter;
+#endif
+#if defined(INTERP_ALPHA)
+                  aLeft += fdaOuter;
+#endif
+#if defined(INTERP_SPEC)
+                  srLeft += dsrOuter;
+                  sgLeft += dsgOuter;
+                  sbLeft += dsbOuter;
 #endif
 #ifdef INTERP_INDEX
-                  fi += fdiOuter;
+                  iLeft += diOuter;
 #endif
 #ifdef INTERP_INT_TEX
-                  fs += fdsOuter;   ft += fdtOuter;
+                  sLeft += dsOuter;
+                  tLeft += dtOuter;
 #endif
 #ifdef INTERP_TEX
-                 sLeft += dsOuter;
-                 tLeft += dtOuter;
-                 uLeft += duOuter;
-                 vLeft += dvOuter;
-#endif
-#ifdef INTERP_MULTITEX
-                  {
-                     GLuint u;
-                     for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
-                        if (ctx->Texture.Unit[u]._ReallyEnabled) {
-                           sLeft[u] += dsOuter[u];
-                           tLeft[u] += dtOuter[u];
-                           uLeft[u] += duOuter[u];
-                           vLeft[u] += dvOuter[u];
-                        }
-                     }
-                  }
+                  TEX_UNIT_LOOP(
+                     sLeft[u] += dsOuter[u];
+                     tLeft[u] += dtOuter[u];
+                     uLeft[u] += duOuter[u];
+                     vLeft[u] += dvOuter[u];
+                  )
 #endif
                }
                else {
 #ifdef PIXEL_ADDRESS
-                  pRow = (PIXEL_TYPE *) ((GLubyte*)pRow + dPRowInner);
+                  pRow = (PIXEL_TYPE *) ((GLubyte *) pRow + dPRowInner);
 #endif
 #ifdef INTERP_Z
 #  ifdef DEPTH_TYPE
-                  zRow = (DEPTH_TYPE *) ((GLubyte*)zRow + dZRowInner);
+                  zRow = (DEPTH_TYPE *) ((GLubyte *) zRow + dZRowInner);
 #  endif
-                  fz += fdzInner;
-                  ffog += fdfogInner;
+                  zLeft += fdzInner;
 #endif
-#ifdef INTERP_RGB
-                  fr += fdrInner;   fg += fdgInner;   fb += fdbInner;
+#ifdef INTERP_W
+                  wLeft += dwInner;
 #endif
-#ifdef INTERP_SPEC
-                  fsr += fdsrInner;   fsg += fdsgInner;   fsb += fdsbInner;
+#ifdef INTERP_FOG
+                  fogLeft += dfogInner;
 #endif
-#ifdef INTERP_ALPHA
-                  fa += fdaInner;
+#if defined(INTERP_RGB)
+                  rLeft += fdrInner;
+                  gLeft += fdgInner;
+                  bLeft += fdbInner;
+#endif
+#if defined(INTERP_ALPHA)
+                  aLeft += fdaInner;
+#endif
+#if defined(INTERP_SPEC)
+                  srLeft += dsrInner;
+                  sgLeft += dsgInner;
+                  sbLeft += dsbInner;
 #endif
 #ifdef INTERP_INDEX
-                  fi += fdiInner;
+                  iLeft += diInner;
 #endif
 #ifdef INTERP_INT_TEX
-                  fs += fdsInner;   ft += fdtInner;
+                  sLeft += dsInner;
+                  tLeft += dtInner;
 #endif
 #ifdef INTERP_TEX
-                 sLeft += dsInner;
-                 tLeft += dtInner;
-                 uLeft += duInner;
-                 vLeft += dvInner;
-#endif
-#ifdef INTERP_MULTITEX
-                  {
-                     GLuint u;
-                     for (u = 0; u < ctx->Const.MaxTextureUnits; u++) {
-                        if (ctx->Texture.Unit[u]._ReallyEnabled) {
-                           sLeft[u] += dsInner[u];
-                           tLeft[u] += dtInner[u];
-                           uLeft[u] += duInner[u];
-                           vLeft[u] += dvInner[u];
-                        }
-                     }
-                  }
+                  TEX_UNIT_LOOP(
+                     sLeft[u] += dsInner[u];
+                     tLeft[u] += dtInner[u];
+                     uLeft[u] += duInner[u];
+                     vLeft[u] += dvInner[u];
+                  )
 #endif
                }
             } /*while lines>0*/
          } /* for subTriangle */
 
       }
+#ifdef CLEANUP_CODE
+      CLEANUP_CODE
+#endif
    }
 }
 
 #undef SETUP_CODE
-#undef INNER_LOOP
+#undef CLEANUP_CODE
+#undef RENDER_SPAN
 
 #undef PIXEL_TYPE
 #undef BYTES_PER_ROW
 #undef PIXEL_ADDRESS
 
 #undef INTERP_Z
+#undef INTERP_W
+#undef INTERP_FOG
 #undef INTERP_RGB
-#undef INTERP_SPEC
 #undef INTERP_ALPHA
+#undef INTERP_SPEC
 #undef INTERP_INDEX
 #undef INTERP_INT_TEX
 #undef INTERP_TEX
 #undef INTERP_MULTITEX
+#undef TEX_UNIT_LOOP
 
 #undef S_SCALE
 #undef T_SCALE
 #undef FixedToDepth
 
 #undef DO_OCCLUSION_TEST
+#undef NAME