Proper font dispatch procs

1 files changed, 146 insertions, 154 deletions

diff --git a/graphics.c b/graphics.c
index 0ed1791..ffe620a 100644
--- a/graphics.c
+++ b/graphics.c
@@ -74,6 +74,10 @@ typedef struct {
 } Pixel_Buffer;
 
 enum {
+  FONT_LCD = 0,
+};
+
+enum {
   GRAPHICS_FILL_TRIANGLE,
   GRAPHICS_FILL_TRIANGLES,
   GRAPHICS_FILL_QUAD,
@@ -137,7 +141,7 @@ typedef struct {
 //
 //  ================================================================
 
-Box dispatch_font_text_area(i32 font, vec2 scale, i64 num_chars, c32 *text);
+vec2 dispatch_font_text_area(i32 font, vec2 scale, i64 num_chars, c32 *text);
 
 void dispatch_font_render_to_stencil(Stencil_Buffer dst, i32 font, vec2 position, vec2 scale, i64 num_chars, c32 *text);
 
@@ -186,6 +190,8 @@ void fill_triangles_to_stencil  (Stencil_Buffer dst, u8 value, vec2 position, ve
 void fill_quad_to_stencil       (Stencil_Buffer dst, u8 value, vec2 vertices[4]);
 void fill_ellipse_to_stencil    (Stencil_Buffer dst, u8 value, Box area);
 void fill_line_to_stencil       (Stencil_Buffer dst, u8 value, vec2 vertices[2], f64 width);
+vec2 lcd_text_area              (vec2 scale, i64 num_chars, c32 *text);
+void lcd_text_render_to_stencil (Stencil_Buffer dst, vec2 position, vec2 scale, i64 num_chars, c32 *text);
 void draw_text_area_to_stencil  (Stencil_Buffer dst, u8 value, i32 font, Box area, vec2 max_size, i64 num_chars, c32 *text);
 void draw_text_cursor_to_stencil(Stencil_Buffer dst, u8 value, i32 font, Box area, vec2 max_size, i64 num_chars, c32 *text, i64 cursor, i64 selection);
 
@@ -622,6 +628,39 @@ Stencil_Buffer default_stencil(i64 width, i64 height) {
   };
 }
 
+static i64 _default_second_stencil_len = 0;
+static u8 *_default_second_stencil     = NULL;
+
+Stencil_Buffer default_second_stencil_(i64 width, i64 height) {
+  i64 len = width * height;
+  if (len < 0)
+    len = 1;
+
+  if (len > _default_second_stencil_len)
+    resize_dynamic_array_exact(&_default_second_stencil_len, (void **) &_default_second_stencil, sizeof *_default_second_stencil, len);
+
+  if (width <= 0 || height <= 0)
+    return (Stencil_Buffer) {
+      .width  = 0,
+      .height = 0,
+      .stride = 1,
+      .pixels = _default_second_stencil,
+    };
+
+  i64 h = height;
+  if (len > _default_second_stencil_len)
+    h = _default_second_stencil_len / width;
+
+  mem_set_(_default_second_stencil, 0, width * h);
+
+  return (Stencil_Buffer) {
+    .width  = width,
+    .height = h,
+    .stride = width,
+    .pixels = _default_second_stencil,
+  };
+}
+
 void fill_stencil_to_stencil(Stencil_Buffer dst, u8 value, Box area, Stencil_Buffer src) {
   i64 x0 = (i64) floor(area.x + 0.5);
   i64 x1 = (i64) floor(area.x + area.width + 0.5);
@@ -1293,30 +1332,6 @@ static i64 lcd_spacing_(i64 num_chars, c32 *text, i64 index) {
   return   !!(_lcd_kerning[a * 2 + 1] & (1ull << (b - 64)));
 }
 
-static i64 lcd_cursor_(i64 num_chars, c32 *text) {
-  if (text == NULL)
-    return 0;
-
-  i64 cursor = 0;
-
-  for (i64 i = 0; i < num_chars; ++i) {
-    if (text[i] <= ' ') {
-      if (text[i] == '\n')
-        cursor = 0;
-      else if (text[i] == '\b' && i > 0)
-        cursor -= lcd_char_width_(text[i - 1]) + lcd_spacing_(num_chars, text, i - 1);
-      else if (text[i] == '\r')
-        cursor = 0;
-      else
-        cursor += lcd_char_width_(' ') + lcd_spacing_(num_chars, text, i);
-      continue;
-    }
-    cursor += lcd_char_width_(text[i]) + lcd_spacing_(num_chars, text, i);
-  }
-
-  return cursor;
-}
-
 static i64 lcd_enum_text_columns_(i64 num_chars, c32 *text) {
   if (text == NULL)
     return 0;
@@ -1330,14 +1345,6 @@ static i64 lcd_enum_text_columns_(i64 num_chars, c32 *text) {
         if (cols < n)
           cols = n;
         n = 0;
-      } else if (text[i] == '\b' && i > 0) {
-        if (cols < n)
-          cols = n;
-        n -= lcd_char_width_(text[i - 1]) + lcd_spacing_(num_chars, text, i - 1);
-      } else if (text[i] == '\r') {
-        if (cols < n)
-          cols = n;
-        n = 0;
       } else
         n += lcd_char_width_(' ') + lcd_spacing_(num_chars, text, i);
       continue;
@@ -1352,7 +1359,7 @@ static i64 lcd_enum_text_columns_(i64 num_chars, c32 *text) {
 }
 
 static i64 lcd_enum_text_rows_(i64 num_chars, c32 *text) {
-  if (text == NULL)
+  if (text == NULL || num_chars == 0)
     return 0;
 
   i64 rows = 0;
@@ -1367,27 +1374,29 @@ static i64 lcd_enum_text_rows_(i64 num_chars, c32 *text) {
   return rows;
 }
 
-static void lcd_draw_text_(Stencil_Buffer dst, u8 value, f64 x0, f64 y0, f64 scale_x, f64 scale_y, i64 num_chars, c32 *text) {
-  f64 kx = scale_x;
-  f64 h  = scale_y * LCD_Height;
+vec2 lcd_text_area(vec2 scale, i64 num_chars, c32 *text) {
+  return (vec2) {
+    .x = scale.x * lcd_enum_text_columns_(num_chars, text),
+    .y = scale.y * lcd_enum_text_rows_   (num_chars, text),
+  };
+}
+
+void lcd_text_render_to_stencil(Stencil_Buffer dst, vec2 position, vec2 scale, i64 num_chars, c32 *text) {
+  f64 kx = scale.x;
+  f64 h  = scale.y * LCD_Height;
 
   if (h < EPSILON)
     return;
 
-  f64 x = x0;
-  f64 y = y0;
+  f64 x = position.x;
+  f64 y = position.y;
 
   for (i64 n = 0; n < num_chars; ++n) {
     if (text[n] <= ' ') {
       if (text[n] == '\n') {
-        x  = x0;
-        y += scale_y * (LCD_Height + 1);
-      }
-      else if (text[n] == '\b' && n > 0)
-        x -= kx * (lcd_char_width_(text[n - 1]) + lcd_spacing_(num_chars, text, n - 1));
-      else if (text[n] == '\r')
-        x  = x0;
-      else
+        x  = position.x;
+        y += scale.y * (LCD_Height + 1);
+      } else
         x += kx * (lcd_char_width_(' ') + lcd_spacing_(num_chars, text, n));
       continue;
     }
@@ -1422,7 +1431,7 @@ static void lcd_draw_text_(Stencil_Buffer dst, u8 value, f64 x0, f64 y0, f64 sca
           u32 column = (((i - i00) * num_cols) * w_inv + w_half) >> 16;
 
           if ((_lcd_bits[index] & (1ull << (row * 8 + column))) != 0)
-            dst.pixels[j * dst.stride + i] = max2_u8_(dst.pixels[j * dst.stride + i], value);
+            dst.pixels[j * dst.stride + i] = max2_u8_(dst.pixels[j * dst.stride + i], 255);
         }
       }
     }
@@ -1432,50 +1441,48 @@ static void lcd_draw_text_(Stencil_Buffer dst, u8 value, f64 x0, f64 y0, f64 sca
 }
 
 #if !defined(ENABLE_FONT_CUSTOM_DISPATCH)
-Box dispatch_font_text_area(i32 font, vec2 scale, i64 num_chars, c32 *text) {
-  //  TODO
-
-  (void) font;
-  (void) scale;
-  (void) num_chars;
-  (void) text;
-
-  return (Box) {0};
+vec2 dispatch_font_text_area(i32 font, vec2 scale, i64 num_chars, c32 *text) {
+  if (font == FONT_LCD)
+    return lcd_text_area(scale, num_chars, text);
+  return (vec2) {0};
 }
 
 void dispatch_font_render_to_stencil(Stencil_Buffer dst, i32 font, vec2 position, vec2 scale, i64 num_chars, c32 *text) {
-  //  TODO
-
-  (void) dst;
-  (void) font;
-  (void) position;
-  (void) scale;
-  (void) num_chars;
-  (void) text;
+  if (font == FONT_LCD)
+    lcd_text_render_to_stencil(dst, position, scale, num_chars, text);
 }
 #endif // !defined(ENABLE_FONT_CUSTOM_DISPATCH)
 
-void draw_text_area_to_stencil(Stencil_Buffer dst, u8 value, i32 font, Box area, vec2 max_size, i64 num_chars, c32 *text) {
-  (void) font;
-
-  if (text == NULL || num_chars <= 0 || max_size.x < EPSILON || max_size.y < EPSILON)
-    return;
-
-  i64 num_columns = lcd_enum_text_columns_(num_chars, text);
-  i64 num_rows    = lcd_enum_text_rows_(num_chars, text);
+static vec2 adjust_text_scale_(i32 font, vec2 area, vec2 max_size, i64 num_chars, c32 *text) {
+  vec2 orig_area = dispatch_font_text_area(font, (vec2) { 1.0, 1.0 }, num_chars, text);
+  if (orig_area.x < EPSILON || orig_area.y < EPSILON)
+    return (vec2) {0};
 
-  f64 scale_x = area.width  / num_columns;
-  f64 scale_y = area.height / num_rows;
+  f64 scale_x = area.x / orig_area.x;
+  f64 scale_y = area.y / orig_area.y;
 
   f64 kx = scale_x / max_size.x;
   f64 ky = scale_y / max_size.y;
 
   f64 k = kx < ky ? kx : ky;
 
-  kx = k * max_size.x;
-  ky = k * max_size.y;
+  return (vec2) { k * max_size.x, k * max_size.y };
+}
 
-  lcd_draw_text_(dst, value, area.x, area.y, kx, ky, num_chars, text);
+void draw_text_area_to_stencil(Stencil_Buffer dst, u8 value, i32 font, Box area, vec2 max_size, i64 num_chars, c32 *text) {
+  (void) font;
+
+  if (text == NULL || num_chars <= 0 || max_size.x < EPSILON || max_size.y < EPSILON)
+    return;
+
+  i64 w = (i64) floor(area.width  + 0.5);
+  i64 h = (i64) floor(area.height + 0.5);
+
+  vec2 scale = adjust_text_scale_(font, (vec2) { area.width, area.height }, max_size, num_chars, text);
+
+  Stencil_Buffer buf = default_second_stencil_(w, h);
+  dispatch_font_render_to_stencil(buf, font, (vec2) {0}, scale, num_chars, text);
+  fill_stencil_to_stencil(dst, value, area, buf);
 }
 
 void draw_text_cursor_to_stencil(Stencil_Buffer dst, u8 value, i32 font, Box area, vec2 max_size, i64 num_chars, c32 *text, i64 cursor, i64 selection) {
@@ -1484,90 +1491,75 @@ void draw_text_cursor_to_stencil(Stencil_Buffer dst, u8 value, i32 font, Box are
   if (max_size.x < EPSILON || max_size.y < EPSILON)
     return;
 
-  i64 num_columns = lcd_enum_text_columns_(num_chars, text);
-  i64 num_rows    = lcd_enum_text_rows_(num_chars, text);
-  i64 cursor_x    = lcd_cursor_(cursor, text);
-  i64 cursor_y    = lcd_enum_text_rows_(cursor, text);
+  if (cursor < 0 || cursor + selection < 0 || cursor > num_chars || cursor + selection > num_chars) {
+    LOG_error("Sanity");
+    return;
+  }
 
-  f64 scale_x = area.width  / num_columns;
-  f64 scale_y = area.height / num_rows;
+  vec2 scale = adjust_text_scale_(font, (vec2) { area.width, area.height }, max_size, num_chars, text);
 
-  f64 kx = scale_x / max_size.x;
-  f64 ky = scale_y / max_size.y;
+  if (selection != 0) {
+    i64 s0 = selection < 0 ? cursor + selection : cursor;
+    i64 s1 = selection > 0 ? cursor + selection : cursor;
 
-  f64 k = kx < ky ? kx : ky;
+    i64 prev_line = 0;
 
-  kx = k * max_size.x;
-  ky = k * max_size.y;
+    for (i64 i0 = 0; i0 < num_chars; ++i0) {
+      i64 i1 = i0;
+      for (; i1 < num_chars && text[i1] != '\n'; ++i1);
 
-  if (selection != 0) {
-    i64 selection_x, selection_y;
+      f64 x0 = 0.0, x1 = -1.0, y0 = 0.0, y1 = -1.0;
 
-    if (selection > 0) {
-      selection_x = lcd_cursor_(cursor + selection, text);
-      selection_y = lcd_enum_text_rows_(cursor + selection, text);
-    } else {
-      selection_x = cursor_x;
-      selection_y = cursor_y;
-      cursor_x    = lcd_cursor_(cursor + selection, text);
-      cursor_y    = lcd_enum_text_rows_(cursor + selection, text);
+      if (s0 >= i0 && s0 < i1) {
+        //  Beginning of the selected fragment.
+
+        x0 = dispatch_font_text_area(font, scale, s0 - i0, text + i0).x;
+        x1 = dispatch_font_text_area(font, scale, i1 - i0, text + i0).x;
+        y0 = dispatch_font_text_area(font, scale, prev_line, text).y + 0.5;
+        y1 = dispatch_font_text_area(font, scale, i1, text).y;
+      }
+
+      if (s1 >= i0 && s1 < i1) {
+        //  Tail of the selected fragment.
+
+        x1 = dispatch_font_text_area(font, scale, s1 - i0, text + i0).x;
+        y0 = dispatch_font_text_area(font, scale, prev_line, text).y + 0.5;
+        y1 = dispatch_font_text_area(font, scale, i1, text).y;
+      }
+
+      if (i0 >= s0 && i1 <= s1) {
+        //  Middle of the selected fragment.
+
+        x1 = dispatch_font_text_area(font, scale, i1 - i0, text + i0).x;
+        y0 = dispatch_font_text_area(font, scale, prev_line, text).y + 0.5;
+        y1 = dispatch_font_text_area(font, scale, i1, text).y;
+      }
+
+      if (x1 - x0 > EPSILON && y1 - y0 > EPSILON)
+        fill_rectangle_to_stencil(dst, value, (Box) { .x = x0, .y = y0, .width = x1 - x0, .height = y1 - y0, });
+
+      prev_line = i1;
+      i0        = i1;
     }
+  } else {
+    f64 x0 = 0.0, x1 = -1.0, y0 = 0.0, y1 = -1.0;
 
-    if (cursor_y == selection_y)
-      fill_rectangle_to_stencil(
-        dst,
-        value,
-        (Box) {
-          .x      = area.x + kx * cursor_x,
-          .y      = area.y + ky * cursor_y - ky * LCD_Height,
-          .width  = kx * (selection_x - cursor_x),
-          .height = ky * (LCD_Height + 1),
-        }
-      );
-    else {
-      fill_rectangle_to_stencil(
-        dst,
-        value,
-        (Box) {
-          .x      = area.x + kx * cursor_x,
-          .y      = area.y + ky * cursor_y - ky * LCD_Height,
-          .width  = kx * (num_columns - cursor_x),
-          .height = ky * (LCD_Height + 1),
-        }
-      );
-      for (i64 j = cursor_y + LCD_Height + 1; j < selection_y; j += LCD_Height + 1)
-        fill_rectangle_to_stencil(
-          dst,
-          value,
-          (Box) {
-            .x      = area.x,
-            .y      = area.y + ky * j - ky * LCD_Height,
-            .width  = kx * num_columns,
-            .height = ky * (LCD_Height + 1),
-          }
-        );
-      fill_rectangle_to_stencil(
-        dst,
-        value,
-        (Box) {
-          .x      = area.x,
-          .y      = area.y + ky * selection_y - ky * LCD_Height,
-          .width  = kx * selection_x,
-          .height = ky * (LCD_Height + 1),
-        }
-      );
+    if (num_chars == 0) {
+      x1 = scale.x;
+      y1 = dispatch_font_text_area(font, scale, 1, (c32[1]) { '|' }).y;
+    } else {
+      i64 i0 = 0;
+      for (i64 i = 0; i < cursor; ++i)
+        if (text[i] == '\n')
+          i0 = i + 1;
+      x0 = dispatch_font_text_area(font, scale, cursor - i0, text + i0).x;
+      x1 = x0 + scale.x;
+      y0 = dispatch_font_text_area(font, scale, i0 > 0 ? i0 - 1 : 0, text).y;
+      y1 = dispatch_font_text_area(font, scale, cursor, text).y;
     }
-  } else
-    fill_rectangle_to_stencil(
-      dst,
-      value,
-      (Box) {
-        .x      = area.x + kx * cursor_x,
-        .y      = area.y + ky * cursor_y - ky * LCD_Height,
-        .width  = kx * 0.5,
-        .height = ky * (LCD_Height - 1),
-      }
-    );
+
+    fill_rectangle_to_stencil(dst, value, (Box) { .x = x0, .y = y0, .width = x1 - x0, .height = y1 - y0, });
+  }
 }
 
 void draw_text_area_to_buffer(Pixel_Buffer dst, vec4_f32 color, i32 font, Box area, vec2 max_size, i64 num_chars, c32 *text, Stencil_Buffer stencil) {
@@ -3151,7 +3143,7 @@ TEST("text cursor") {
     0, 0, 0, 0, 1, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 1, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 1, 0, 0, 0, 0, 0,
-    0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+    0, 0, 0, 0, 1, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     0, 0, 0, 0, 0, 0, 0, 0, 0, 0,