added invert switch to support black on white terminals

diff --git a/include/viewer.h b/include/viewer.h
index 5175414..68c7a13 100644 (file)
--- a/include/viewer.h
+++ b/include/viewer.h
@@ -44,10 +44,10 @@
 
 #define FADE_DELAY 15000 // micro seconds
 
-int ncurses_display(deck_t *deck, int notrans, int nofade);
+int ncurses_display(deck_t *deck, int notrans, int nofade, int invert);
 void add_line(WINDOW *window, int y, int x, line_t *line, int max_cols, int colors);
-void fade_out(WINDOW *window, int trans, int colors);
-void fade_in(WINDOW *window, int trans, int colors);
+void fade_out(WINDOW *window, int trans, int colors, int invert);
+void fade_in(WINDOW *window, int trans, int colors, int invert);
 int int_length (int val);
 
 #endif // !defined( VIEWER_H )

diff --git a/mdp.c b/mdp.c
index 4e37879..3bf1bd2 100644 (file)
--- a/mdp.c
+++ b/mdp.c
@@ -32,6 +32,7 @@ void usage() {
     fprintf(stderr, "%s", "                  add it multiple times to increases debug level\n");
     fprintf(stderr, "%s", "  -f, --nofade    disable color fading in 256 color mode\n");
     fprintf(stderr, "%s", "  -h, --help      display this help and exit\n");
+    fprintf(stderr, "%s", "  -i, --invert    swap black and white color\n");
     fprintf(stderr, "%s", "  -t, --notrans   disable transparency in transparent terminal\n");
     fprintf(stderr, "%s", "\nWith no FILE, or when FILE is -, read standard input.\n\n");
     exit(EXIT_FAILURE);
@@ -50,12 +51,14 @@ void version() {
 int main(int argc, char *argv[]) {
     int notrans = 0;
     int nofade = 0;
+    int invert = 0;
 
     // define command-line options
     struct option longopts[] = {
         { "debug",   no_argument, 0, 'd' },
         { "nofade",  no_argument, 0, 'f' },
         { "help",    no_argument, 0, 'h' },
+        { "invert",  no_argument, 0, 'i' },
         { "notrans", no_argument, 0, 't' },
         { "version", no_argument, 0, 'v' },
         { 0, 0, 0, 0 }
@@ -63,11 +66,12 @@ int main(int argc, char *argv[]) {
 
     // parse command-line options
     int opt, debug = 0;
-    while ((opt = getopt_long(argc, argv, ":dfhtv", longopts, NULL)) != -1) {
+    while ((opt = getopt_long(argc, argv, ":dfhitv", longopts, NULL)) != -1) {
         switch(opt) {
             case 'd': debug += 1; break;
             case 'f': nofade = 1; break;
             case 'h': usage(); break;
+            case 'i': invert = 1; break;
             case 't': notrans = 1; break;
             case 'v': version(); break;
             case ':': fprintf(stderr, "%s: '%c' requires an argument\n", argv[0], optopt); usage(); break;
@@ -112,7 +116,7 @@ int main(int argc, char *argv[]) {
         markdown_debug(deck, debug);
     }
 
-    ncurses_display(deck, notrans, nofade);
+    ncurses_display(deck, notrans, nofade, invert);
 
     return(EXIT_SUCCESS);
 }

diff --git a/viewer.c b/viewer.c
index 793e4da..49b61eb 100644 (file)
--- a/viewer.c
+++ b/viewer.c
@@ -29,14 +29,15 @@
 
 #include "include/viewer.h"
 
+// color ramp for fading from black to color
 static short white_ramp[24] = { 16, 232, 233, 234, 235, 236,
                                237, 238, 239, 240, 241, 242,
                                244, 245, 246, 247, 248, 249,
                                250, 251, 252, 253, 254, 255 };
 
 static short blue_ramp[24]  = { 16,  17,  17,  18,  18,  19,
-                                19,  20,  20,  21,  27,  32,
-                                33,  38,  39,  44,  45,  45,
+                                19,  20,  20,  21,  27,  33,
+                                32,  39,  38,  45,  44,  44,
                                 81,  81,  51,  51, 123, 123 };
 
 static short red_ramp[24]   = { 16,  52,  52,  53,  53,  89,
@@ -44,7 +45,23 @@ static short red_ramp[24]   = { 16,  52,  52,  53,  53,  89,
                                163, 163, 164, 164, 200, 200,
                                201, 201, 207, 207, 213, 213 };
 
-int ncurses_display(deck_t *deck, int notrans, int nofade) {
+// color ramp for fading from white to color
+static short white_ramp_invert[24] = { 15, 255, 254, 254, 252, 251,
+                                      250, 249, 248, 247, 246, 245,
+                                      243, 242, 241, 240, 239, 238,
+                                      237, 236, 235, 234, 233, 232};
+
+static short blue_ramp_invert[24]  = { 15, 231, 231, 195, 195, 159,
+                                      159, 123, 123,  87,  51,  44,
+                                       45,  38,  39,  32,  33,  33,
+                                       26,  26,  27,  27,  21,  21};
+
+static short red_ramp_invert[24]   = { 15, 231, 231, 224, 224, 225,
+                                      225, 218, 218, 219, 212, 213,
+                                      206, 207, 201, 200, 199, 199,
+                                      198, 198, 197, 197, 196, 196};
+
+int ncurses_display(deck_t *deck, int notrans, int nofade, int invert) {
 
     int c = 0;          // char
     int i = 0;          // iterate
@@ -110,23 +127,47 @@ int ncurses_display(deck_t *deck, int notrans, int nofade) {
         start_color();
         use_default_colors();
 
-        if(notrans) trans = 0; // black in 8 color mode
-
+        // 256 color mode
         if(COLORS == 256) {
-            if(notrans) trans = 16; // black in 256 color mode
 
-            // 256 color mode
-            init_pair(CP_WHITE, 255, trans);
-            init_pair(CP_BLUE, 123, trans);
-            init_pair(CP_RED, 213, trans);
+            if(notrans) {
+                if(invert) {
+                    trans = 15; // white in 256 color mode
+                } else {
+                    trans = 16; // black in 256 color mode
+                }
+            }
+
+            if(invert) {
+                init_pair(CP_WHITE, 232, trans);
+                init_pair(CP_BLUE, 21, trans);
+                init_pair(CP_RED, 196, trans);
+            } else {
+                init_pair(CP_WHITE, 255, trans);
+                init_pair(CP_BLUE, 123, trans);
+                init_pair(CP_RED, 213, trans);
+            }
             init_pair(CP_YELLOW, 208, trans);
 
             // enable color fading
             if(!nofade) fade = 1;
+
+        // 8 color mode
         } else {
 
-            // 8 color mode
-            init_pair(CP_WHITE, 7, trans);
+            if(notrans) {
+                if(invert) {
+                    trans = 7; // white in 8 color mode
+                } else {
+                    trans = 0; // black in 8 color mode
+                }
+            }
+
+            if(invert) {
+                init_pair(CP_WHITE, 0, trans);
+            } else {
+                init_pair(CP_WHITE, 7, trans);
+            }
             init_pair(CP_BLUE, 4, trans);
             init_pair(CP_RED, 1, trans);
             init_pair(CP_YELLOW, 3, trans);
@@ -195,7 +236,7 @@ int ncurses_display(deck_t *deck, int notrans, int nofade) {
 
         // fade in
         if(fade)
-            fade_in(content, trans, colors);
+            fade_in(content, trans, colors, invert);
 
         // re-enable fading after any undefined key press
         if(COLORS == 256 && !nofade) fade = 1;
@@ -297,7 +338,7 @@ int ncurses_display(deck_t *deck, int notrans, int nofade) {
 
         // fade out
         if(fade)
-            fade_out(content, trans, colors);
+            fade_out(content, trans, colors, invert);
     }
 
     endwin();
@@ -466,32 +507,50 @@ void add_line(WINDOW *window, int y, int x, line_t *line, int max_cols, int colo
     (stack->delete)(stack);
 }
 
-void fade_out(WINDOW *window, int trans, int colors) {
+void fade_out(WINDOW *window, int trans, int colors, int invert) {
     int i; // increment
     if(colors) {
         for(i = 22; i >= 0; i--) {
-            // darken color pairs
-            init_pair(CP_WHITE, white_ramp[i], trans);
-            init_pair(CP_BLUE, blue_ramp[i], trans);
-            init_pair(CP_RED, red_ramp[i], trans);
+
+            // dim color pairs
+            if(invert) {
+                init_pair(CP_WHITE, white_ramp_invert[i], trans);
+                init_pair(CP_BLUE, blue_ramp_invert[i], trans);
+                init_pair(CP_RED, red_ramp_invert[i], trans);
+            } else {
+                init_pair(CP_WHITE, white_ramp[i], trans);
+                init_pair(CP_BLUE, blue_ramp[i], trans);
+                init_pair(CP_RED, red_ramp[i], trans);
+            }
+
             // refresh window with new color
             wrefresh(window);
+
             // delay for our eyes to recognize the change
             usleep(FADE_DELAY);
         }
     }
 }
 
-void fade_in(WINDOW *window, int trans, int colors) {
+void fade_in(WINDOW *window, int trans, int colors, int invert) {
     int i; // increment
     if(colors) {
         for(i = 0; i <= 23; i++) {
-            // lighten color pairs
-            init_pair(CP_WHITE, white_ramp[i], trans);
-            init_pair(CP_BLUE, blue_ramp[i], trans);
-            init_pair(CP_RED, red_ramp[i], trans);
+
+            // brighten color pairs
+            if(invert) {
+                init_pair(CP_WHITE, white_ramp_invert[i], trans);
+                init_pair(CP_BLUE, blue_ramp_invert[i], trans);
+                init_pair(CP_RED, red_ramp_invert[i], trans);
+            } else {
+                init_pair(CP_WHITE, white_ramp[i], trans);
+                init_pair(CP_BLUE, blue_ramp[i], trans);
+                init_pair(CP_RED, red_ramp[i], trans);
+            }
+
             // refresh window with new color
             wrefresh(window);
+
             // delay for our eyes to recognize the change
             usleep(FADE_DELAY);
         }