Continuing to work on status bar

Author: devinsmith

src/lib/engine.c

@@ -4141,7 +4141,7 @@ static void draw_player_status(uint8_t val)
     word_36C2 = 0x4E; // ending point
 
     while (1) {
-      ui_draw_solid_color(fill_color, word_36C0, word_36C2, g_linenum);
+      ui_draw_horizontal_line(fill_color, word_36C0, word_36C2, g_linenum);
       g_linenum++;
 
       if ((g_linenum & 0x0F) == 0) {
@@ -4225,9 +4225,9 @@ static void draw_player_status(uint8_t val)
     word_36C0 = 0x36;
     word_36C2 = 0x4E;
     // 0x1B87
-    ui_draw_solid_color(fill_color, word_36C0, word_36C2, g_linenum);
+    ui_draw_horizontal_line(fill_color, word_36C0, word_36C2, g_linenum);
     g_linenum -= 3;
-    ui_draw_solid_color(fill_color, word_36C0, word_36C2, g_linenum);
+    ui_draw_horizontal_line(fill_color, word_36C0, word_36C2, g_linenum);
     reset_ui_background();
     return;
   }
@@ -6532,11 +6532,14 @@ static void sub_11A0(int set_11C4)
 }
 
 // Input is 11C0, 11C6, 11C8
+// Output is 11CA, 11CC
 static void sub_11CE()
 {
   int old_carry = 0;
   int carry = 0;
 
+  printf("%s (input): 0x%04X 0x%04X 0x%04X\n", __func__, word_11C0, word_11C6, word_11C8);
+
   word_11CA = 0;
   word_11CC = 0;
   cpu.cx = 0x20; // 32 times.
@@ -6589,15 +6592,6 @@ static void sub_11CE()
   }
 }
 
-// 0x1C49
-static void sub_1C49(uint16_t fill_color)
-{
-  // Does this order matter? It seems more natural to draw lines from top
-  // to bottom, but this matches how the game did it.
-  ui_draw_solid_color(fill_color, word_36C0, word_36C2, g_linenum + 1);
-  ui_draw_solid_color(fill_color, word_36C0, word_36C2, g_linenum);
-}
-
 static void sub_1BF8(uint8_t color, uint8_t y_adjust)
 {
   uint16_t fill_color;
@@ -6608,28 +6602,32 @@ static void sub_1BF8(uint8_t color, uint8_t y_adjust)
   if (sub_1C57(cpu.bx) != 0) {
     cpu.bx += 2; // now check max?
     push_word(cpu.bx);
-    word_11C2 = 0x17;
+    word_11C2 = 0x17; // max percentage?
     sub_11A0(0);
     cpu.bx = pop_word();
     if (sub_1C57(cpu.bx) != 0) {
+      // Calculate percentage of 0x17 that ratio is.
       sub_11CE();
       cpu.ax = word_11C6;
       cpu.ax++;
     }
   }
+
+  // Draw color portion of status bar.
+  word_36C0 = 0x36;
   cpu.ax += 0x36;
   word_36C2 = cpu.ax;
-  word_36C0 = 0x36;
-  sub_1C49(fill_color);
+  ui_draw_double_horizontal_line(fill_color, word_36C0, word_36C2, g_linenum);
   cpu.ax = word_36C2;
   if (cpu.ax == 0x4E) {
     return;
   }
 
   // 1C3A
+  // Draw remaining black part of status bar.
   word_36C0 = cpu.ax;
   word_36C2 = 0x4E;
   fill_color = byte_1BE5; // color.
-  sub_1C49(fill_color);
+  ui_draw_double_horizontal_line(fill_color, word_36C0, word_36C2, g_linenum);
 }
 

src/lib/ui.c

@@ -571,27 +571,44 @@ void draw_ui_piece(const struct pic_data *pic)
   vga_update();
 }
 
+// 0x1C49
+/* Draws two horizontal lines across the frame buffer in the specified color,
+ * from x1 -> x2 on line y, and y+1 */
+void ui_draw_double_horizontal_line(
+  uint8_t color_idx,
+  uint16_t x1, uint16_t x2,
+  uint16_t y)
+{
+  // Does this order matter? It seems more natural to draw lines from top
+  // to bottom, but this matches how the game did it.
+  ui_draw_horizontal_line(color_idx, x1, x2, y + 1);
+  ui_draw_horizontal_line(color_idx, x1, x2, y);
+}
+
 /* 0x36C8 */
-void ui_draw_solid_color(uint8_t color_idx, uint16_t inset,
-    uint16_t count, uint16_t line_num)
+/* Draws a horizontal line across the frame buffer in the specified color,
+ * from x1 -> x2 on line y */
+void ui_draw_horizontal_line(
+    uint8_t color_idx,
+    uint16_t x1, uint16_t x2,
+    uint16_t y)
 {
-  // early exit.
-  if (count <= inset) {
+  // We only support drawing left to right.
+  if (x2 <= x1) {
     return;
   }
-  count -= inset;
-  count = count << 1;
+
+  uint16_t len = x2 - x1;
+  len = len << 1;
 
   // bx = color
-  uint8_t color = color_data[color_idx];
-  color = color & 0x0F;
+  uint8_t color = color_data[color_idx] & 0x0F;
 
-  uint16_t fb_off = get_line_offset(line_num);
-  inset = inset << 2;
-  fb_off += inset;
-  uint8_t *framebuffer = vga_memory();
+  uint16_t fb_off = get_line_offset(y);
+  fb_off += (x1 << 2);
 
-  for (uint16_t i = 0; i < count; i++) {
+  uint8_t *framebuffer = vga_memory();
+  for (uint16_t i = 0; i < len; i++) {
     framebuffer[fb_off++] = color;
     framebuffer[fb_off++] = color;
   }

src/lib/ui.h

@@ -80,8 +80,17 @@ void sub_35A0(uint8_t piece_index);
 void draw_pattern(struct ui_rect *rect);
 void ui_set_background(uint16_t val);
 void ui_draw_string(void);
-void ui_draw_solid_color(uint8_t color, uint16_t line_num,
-    uint16_t inset, uint16_t count);
+
+void ui_draw_horizontal_line(
+  uint8_t color_idx,
+  uint16_t x1, uint16_t x2,
+  uint16_t y);
+
+void ui_draw_double_horizontal_line(
+  uint8_t color_idx,
+  uint16_t x1, uint16_t x2,
+  uint16_t y);
+
 void draw_right_pillar();
 void reset_ui_background();