font rendering

1 files changed, 58 insertions, 3 deletions

diff --git a/txtgameengine/fonts.py b/txtgameengine/fonts.py
index fcbf8b5..afa9d87 100644
--- a/txtgameengine/fonts.py
+++ b/txtgameengine/fonts.py
@@ -5,12 +5,16 @@ from typing import Optional
 import typing
 import xml.dom.minidom as minidom
 
+from .shaders import FontShader
+
 if typing.TYPE_CHECKING:
     from .twod import Texture
     from .app import TxtGameApp
 
 
 class Font(ABC):
+    texture: 'Texture'
+
     def __init__(self):
         self.glyphs = dict()
 
@@ -31,14 +35,15 @@ class Glyph:
 
 
 class BitmapFont(Font):
-    def __init__(self, texture: Texture, xml_path: str):
+    def __init__(self, texture: 'Texture', xml_path: str):
+        super().__init__()
         self.texture = texture
-        dom = minidom.parse(xml_path)
+        dom = minidom.parse(str(xml_path))
         for char in dom.getElementsByTagName('Char'):
             code = char.attributes['code'].value
             width = char.attributes['width'].value
             x_render_offset, y_render_offset = char.attributes['offset'].value.split(' ')
-            x_texture_offset, y_texture_offset, x_texture_width, y_texture_width = char.attributes['rect'].split(' ')
+            x_texture_offset, y_texture_offset, x_texture_width, y_texture_width = char.attributes['rect'].value.split(' ')
             self.glyphs[code] = \
                 Glyph(self, int(x_texture_offset), int(y_texture_offset), int(x_texture_width), int(y_texture_width),
                       int(x_render_offset), int(y_render_offset), int(width))
@@ -48,10 +53,60 @@ class BitmapFont(Font):
         from .twod import Texture
         return cls(Texture(app, image_path), xml_path)
 
+    @classmethod
+    def fira_mono(cls, app: 'TxtGameApp'):
+        from .app import builtin_resource_path
+        return cls.load(app, builtin_resource_path / 'fonts/fira_code/regular.png',
+                        builtin_resource_path / 'fonts/fira_code/regular.xml')
+
 
 class TextRenderer:
     def __init__(self, app: 'TxtGameApp'):
         self.app = app
+        self.font: Font = None
+        self.shader = FontShader(app)
 
     def use_font(self, font: Font):
         self.font = font
+
+    def render_text(self, x: int, y: int, text: str) -> typing.Tuple[int, int]:
+        """No support for newlines"""
+        if self.font is None:
+            raise ValueError("No font set")
+        glyphs = list(map(self.font.get_glyph, text))
+        missing = [t for t, g in zip(text, glyphs) if g is None]
+        if missing:
+            raise ValueError("No glyph found for character '%s'" % missing[0])
+        with self.shader:
+            self.app.render.bind_texture(self.shader.textureSampler, self.font.texture)
+            for glyph in glyphs:
+                x, y = self._render_glyph(glyph, x, y)
+        return x, y
+
+    def _render_glyph(self, glyph: Glyph, x: int, y: int) -> typing.Tuple[int, int]:
+        low_x = x + glyph.x_render_offset
+        high_x = low_x + glyph.x_texture_width
+        low_y = y + glyph.y_render_offset
+        high_y = low_y + glyph.y_texture_width
+        low_x, low_y = self.app.coords.from_pixels_to_screen(low_x, low_y)
+        high_x, high_y = self.app.coords.from_pixels_to_screen(high_x, high_y)
+        tex_low_x = glyph.x_texture_offset
+        tex_high_x = tex_low_x + glyph.x_texture_width
+        tex_low_y = glyph.y_texture_offset
+        tex_high_y = tex_low_y + glyph.y_texture_width
+        tex_low_x, tex_low_y = self.app.coords.from_pixels_to_screen(tex_low_x, tex_low_y)
+        tex_high_x, tex_high_y = self.app.coords.from_pixels_to_screen(tex_high_x, tex_high_y)
+        render = self.app.render.setup_buffer([
+            low_x, low_y,
+            high_x, low_y,
+            low_x, high_y,
+            high_x, high_y,
+        ])
+        uvs = self.app.render.setup_buffer([
+            tex_low_x, tex_low_y,
+            tex_high_x, tex_low_y,
+            tex_low_x, tex_high_y,
+            tex_high_x, tex_high_y,
+        ])
+        self.app.render.textured_triangle(render, uvs, 4)
+        return x + glyph.x_advance, y