Remove 'alpha' field from gx_device_color.

This field is set to gx_max_color_value on creation. It is then
encoded/decoded, copied around and serialised/deserialised, but
can never actually be set to any other value.

Strip out the code that knocks on from this.

4 files changed, 1 insertions, 45 deletions

diff --git a/base/gdevplnx.c b/base/gdevplnx.c
index 52b490b8f..58c3da2f7 100644
--- a/base/gdevplnx.c
+++ b/base/gdevplnx.c
@@ -185,9 +185,7 @@ reduce_drawing_color(gx_device_color *ppdc, gx_device_plane_extract *edev,
             gx_devn_reduce_colored_halftone(ppdc, (gx_device *)edev);
             ppdc->colors.pure = COLOR_PIXEL(edev, ppdc->colors.pure);
             reduced = REDUCE_PURE(edev, gx_dc_pure_color(ppdc));
-        } else if (ppdc->colors.colored.alpha != gx_max_color_value)
-            return REDUCE_FAILED; /* can't reduce */
-        else {
+        } else {
             gx_devn_reduce_colored_halftone(ppdc, (gx_device *)edev);
             ppdc->colors.binary.color[0] =
                 COLOR_PIXEL(edev, ppdc->colors.binary.color[0]);
diff --git a/base/gsdcolor.h b/base/gsdcolor.h
index 367dcd487..253799ede 100644
--- a/base/gsdcolor.h
+++ b/base/gsdcolor.h
@@ -271,7 +271,6 @@ struct gx_device_color_s {
             ushort num_components;
             byte c_base[GX_DEVICE_COLOR_MAX_COMPONENTS];
             uint c_level[GX_DEVICE_COLOR_MAX_COMPONENTS];
-            ushort /*gx_color_value */ alpha;
 #if GX_DEVICE_COLOR_MAX_COMPONENTS <= ARCH_SIZEOF_SHORT * 8
             ushort plane_mask;
 #else
@@ -371,7 +370,6 @@ struct gx_device_color_saved_s {
         struct _svcol {
             byte    c_base[GX_DEVICE_COLOR_MAX_COMPONENTS];
             uint    c_level[GX_DEVICE_COLOR_MAX_COMPONENTS];
-            ushort  alpha;
         }               colored;
         struct _svdevn {
             ushort values[GX_DEVICE_COLOR_MAX_COMPONENTS];
diff --git a/base/gxcht.c b/base/gxcht.c
index fa40565a3..ed9868d37 100644
--- a/base/gxcht.c
+++ b/base/gxcht.c
@@ -85,7 +85,6 @@ gx_dc_ht_colored_save_dc(const gx_device_color * pdevc,
     memcpy( psdc->colors.colored.c_level,
             pdevc->colors.colored.c_level,
             sizeof(psdc->colors.colored.c_base) );
-    psdc->colors.colored.alpha = pdevc->colors.colored.alpha;
     psdc->phase = pdevc->phase;
 }
 
@@ -105,7 +104,6 @@ gx_dc_ht_colored_equal(const gx_device_color * pdevc1,
 
     if (pdevc2->type != pdevc1->type ||
         pdevc1->colors.colored.c_ht != pdevc2->colors.colored.c_ht ||
-        pdevc1->colors.colored.alpha != pdevc2->colors.colored.alpha ||
         pdevc1->phase.x != pdevc2->phase.x ||
         pdevc1->phase.y != pdevc2->phase.y ||
         num_comp != pdevc2->colors.colored.num_components
@@ -133,8 +131,6 @@ gx_dc_ht_colored_equal(const gx_device_color * pdevc1,
  */
 static const int   dc_ht_colored_has_base = 0x01;
 static const int   dc_ht_colored_has_level = 0x02;
-static const int   dc_ht_colored_has_alpha = 0x04;
-static const int   dc_ht_colored_alpha_is_max = 0x08;
 
 /*
  * Serialize a device color that uses a traditional colored halftone.
@@ -196,7 +192,6 @@ gx_dc_ht_colored_write(
     int                             num_comps = dev->color_info.num_components;
     int                             depth = dev->color_info.depth;
     gx_color_index                  plane_mask = pdevc->colors.colored.plane_mask;
-    gx_color_value                  alpha = pdevc->colors.colored.alpha;
     const gx_device_color_saved *   psdc = psdc0;
     byte *                          pdata0 = pdata;
 
@@ -248,15 +243,6 @@ gx_dc_ht_colored_write(
         }
     }
 
-    if (psdc == 0 || alpha != psdc->colors.colored.alpha) {
-        if (alpha == gx_max_color_value)
-            flag_bits |= dc_ht_colored_alpha_is_max;
-        else {
-            flag_bits |= dc_ht_colored_has_alpha;
-            req_size += enc_u_sizew(alpha);
-        }
-    }
-
     /* see if there is anything to do */
     if (flag_bits == 0) {
         *psize = 0;
@@ -313,9 +299,6 @@ gx_dc_ht_colored_write(
         }
     }
 
-    if ((flag_bits & dc_ht_colored_has_alpha) != 0)
-        enc_u_putw(alpha, pdata);
-
     *psize = pdata - pdata0;
     return 0;
 }
@@ -447,17 +430,6 @@ gx_dc_ht_colored_read(
         size -= pdata - pdata_start;
     }
 
-    if ((flag_bits & dc_ht_colored_alpha_is_max) != 0)
-        devc.colors.colored.alpha = gx_max_color_value;
-    else if ((flag_bits & dc_ht_colored_has_alpha) != 0) {
-        const byte *    pdata_start = pdata;
-
-        if (size < 1)
-            return_error(gs_error_rangecheck);
-        enc_u_getw(devc.colors.colored.alpha, pdata);
-        size -= pdata - pdata_start;
-    }
-
     /* set the phase as required (select value is arbitrary) */
     color_set_phase_mod( &devc,
                          pgs->screen_phase[0].x,
@@ -871,9 +843,6 @@ set_ht_colors_le_4(color_values_pair_t *pvp /* only used internally */,
         set_plane_color(2, pvp, pdc, sbits, caches, max_color, invert);
     }
     if (nplanes == 3) {
-        gx_color_value alpha = pdc->colors.colored.alpha;
-
-        if (alpha == gx_max_color_value) {
 #define M(i)\
   cvalues[0] = pvp->values[(i) & 1][0];\
   cvalues[1] = pvp->values[((i) & 2) >> 1][1];\
@@ -882,14 +851,6 @@ set_ht_colors_le_4(color_values_pair_t *pvp /* only used internally */,
 
             M(0); M(1); M(2); M(3); M(4); M(5); M(6); M(7);
 #undef M
-        } else {
-#define M(i)\
-  colors[i] = dev_proc(dev, map_rgb_alpha_color)(dev, pvp->values[(i) & 1][0],\
-                                     pvp->values[((i) & 2) >> 1][1],\
-                                     pvp->values[(i) >> 2][2], alpha)
-            M(0); M(1); M(2); M(3); M(4); M(5); M(6); M(7);
-#undef M
-        }
     } else if (nplanes > 3){
         set_plane_color(3, pvp, pdc, sbits, caches, max_color, invert);
         if (nplanes > 4) {
diff --git a/base/gxdcolor.c b/base/gxdcolor.c
index dbd1b57bc..87de80019 100644
--- a/base/gxdcolor.c
+++ b/base/gxdcolor.c
@@ -1026,7 +1026,6 @@ gx_complete_halftone(gx_device_color *pdevc, int num_comps, gx_device_halftone *
     pdevc->type = gx_dc_type_ht_colored;
     pdevc->colors.colored.c_ht = pdht;
     pdevc->colors.colored.num_components = num_comps;
-    pdevc->colors.colored.alpha = max_ushort;
     for (i = 0; i < num_comps; i++)
         mask |= ((pdevc->colors.colored.c_level[i] != 0 ? 1 : 0) << i);
     pdevc->colors.colored.plane_mask = mask;