color loop for gd.trm

[Shigeharu T. <sh...@ie...>]

shige 10/07 2005
----------------

The following patch do use small number of colors in gd.trm. This
enables to set simply the same colors as in x11 term by:

  set term png colorloop xffffff x000000 x404040 \
  xff0000 x00ff00 x0000ff xff00ff x00ffff xa0522d xffa500 xff7f50

or as in win term by:

  set term gif colorloop xffffff x000000 x404040 \
  xff0000 x00ff00 x0000ff xff00ff x000080 \
  x800000 x008080 x000000 x808080 x008040 \
  x808000 x800080 xc0c0c0 x00ffff xffff00

Although png term use 256 colors even if the number of colors was 
given explicitly, the colorloop option tells gnuplot to use only 
specified colors.

----- From here -----
--- gd.trm.ORG	Sat Sep 24 15:42:05 2005
+++ gd.trm	Fri Oct  7 20:48:34 2005
@@ -101,6 +101,8 @@
  *                          added support for line width and TrueType fonts
  */
 
+#define COLORLOOP
+
 #include "driver.h"
 
 #ifdef TERM_REGISTER
@@ -221,6 +223,9 @@
     PNG_TRUECOLOR, PNG_NOTRUECOLOR,
     PNG_LINEWIDTH,
     GIF_ANIMATE, GIF_DELAY, GIF_LOOP, GIF_NOOPT,
+#ifdef COLORLOOP
+    PNG_COLORLOOP,
+#endif
     PNG_OTHER
 };
 
@@ -233,6 +238,9 @@
 static int PNG_YMAX = GREG_YMAX;
 static const int PNG_POINT_SCALE = 3;
 static int PNG_ps = 3;
+#ifdef COLORLOOP
+static int PNG_color_loop = FALSE;
+#endif
 
 static struct gen_table PNG_opts[] =
 {
@@ -259,6 +267,9 @@
     { "loop", GIF_LOOP },
     { "noopt$imize", GIF_NOOPT }, /* end of gif animation options */
     { "lw", PNG_LINEWIDTH },
+#ifdef COLORLOOP
+    { "colorloop", PNG_COLORLOOP },
+#endif
     { NULL, PNG_OTHER }
 };
 
@@ -694,6 +705,12 @@
 	    png_state.frame_optimization = FALSE;
 	    gif_anim_option = 1;
 	    break;
+#ifdef COLORLOOP
+	case PNG_COLORLOOP:
+	    PNG_color_loop = TRUE;
+	    c_token++;
+	    break;
+#endif
 
 	case PNG_OTHER:
 	default:
@@ -839,6 +856,9 @@
 
     sprintf(term_options + strlen(term_options),
 	    "size %d,%d ", PNG_XMAX, PNG_YMAX);
+#ifdef COLORLOOP
+    if(PNG_color_loop) strcat(term_options,"color_loop ");
+#endif
 
     for (i = 0; strlen(term_options) + 9 < MAX_LINE_LEN &&
            i < png_state.n_colors; i++) {
@@ -1156,8 +1176,13 @@
 	    (web_color_rgbs[i].r << 16) |
 	    (web_color_rgbs[i].g << 8) |
 	    web_color_rgbs[i].b;
+#ifdef COLORLOOP
+    if (PNG_color_loop == FALSE && png_state.n_colors < WEB_N_COLORS)
+	png_state.n_colors = WEB_N_COLORS;
+#else
     if (png_state.n_colors < WEB_N_COLORS)
 	png_state.n_colors = WEB_N_COLORS;
+#endif
     for (i = 0; i < png_state.n_colors; i++) {
 	rgb = png_state.rgb_table[i];
 	png_state.color_table[i] =
----- To here ------

+========================================================+
 Shigeharu TAKENO     NIigata Institute of Technology
                       kashiwazaki,Niigata 945-1195 JAPAN
 sh...@ie...   TEL(&FAX): +81-257-22-8161
+========================================================+