fixed width font => variable width font

1 files changed, 30 insertions, 8 deletions

diff --git a/fonts.c b/fonts.c
index 7704a7d..c13e1fe 100644
--- a/fonts.c
+++ b/fonts.c
@@ -3,6 +3,23 @@
 
 #include "fonts.h"
 
+void init_symbols_boundaries()
+{
+  // space needs special treatment
+  symbols_boundaries[0][0] = 0;
+  symbols_boundaries[0][1] = MAX_SYMBOL_WIDTH - 1;
+  for (int i = 1; i < SYMBOL_COUNT; i++) {
+    symbols_boundaries[i][0] = -1;
+    symbols_boundaries[i][1] = -1;
+    for (int j = 0; j < MAX_SYMBOL_WIDTH; j++) {
+      if ((symbols_boundaries[i][0] == -1) && (symbols[i * MAX_SYMBOL_WIDTH + j] != 0x00))
+        symbols_boundaries[i][0] = j;
+      if ((symbols_boundaries[i][1] == -1) && (symbols[i * MAX_SYMBOL_WIDTH + MAX_SYMBOL_WIDTH - 1 - j] != 0x00))
+        symbols_boundaries[i][1] = MAX_SYMBOL_WIDTH - 1 - j;
+    }
+  }
+}
+
 int skip_gaps(char16_t *operand)
 {
   for (int i=sizeof(skip_ranges)/sizeof(skip_ranges[0])-1; i>=0; i--) {
@@ -12,7 +29,7 @@ int skip_gaps(char16_t *operand)
       return 1;
     *operand -= skip_ranges[i][1] - skip_ranges[i][0] + 1;
   }
-  if ((*operand < 0) || (*operand >= (sizeof(symbols) / SYMBOL_WIDTH)))
+  if ((*operand < 0) || (*operand >= SYMBOL_COUNT))
     return 1;
   return 0;
 }
@@ -21,7 +38,7 @@ int render(char *input, int input_len, char *output, int max_output_len, int ski
 {
   memset(output, 0, max_output_len);
   int output_i = 0;
-  for (int input_i=0; (input_i < input_len) && (output_i*(SYMBOL_WIDTH+1) < max_output_len) && input[input_i]; input_i++) {
+  for (int input_i=0; (input_i < input_len) && (output_i < max_output_len) && input[input_i]; input_i++) {
     char16_t c = (unsigned char)input[input_i];
     if ((c == 0xc2) || (c == 0xc3)) {
       input_i++;
@@ -30,15 +47,20 @@ int render(char *input, int input_len, char *output, int max_output_len, int ski
       c = (c << 8) | (unsigned char)input[input_i];
     }
     if (skip_gaps(&c)) {
-      output_i += !!skip_unprintables;
-      continue;
+      if (skip_unprintables)
+        continue;
+      c = 0x00; // space
+    }
+    for (int i = symbols_boundaries[c][0]; i <= symbols_boundaries[c][1]; i++) {
+      if (output_i >= max_output_len)
+        break;
+      output[output_i] = symbols[c * MAX_SYMBOL_WIDTH + i];
+      output_i++;
     }
-    for (int i=0; (i<SYMBOL_WIDTH) && (output_i*(SYMBOL_WIDTH+1) + i < max_output_len); i++)
-      output[output_i*(SYMBOL_WIDTH+1) + i] = symbols[c*SYMBOL_WIDTH + i];
     output_i++;
   }
-  if (output_i*(SYMBOL_WIDTH+1) >= max_output_len)
+  if (output_i >= max_output_len)
     return max_output_len;
   else
-    return output_i*(SYMBOL_WIDTH+1);
+    return output_i;
 }