Working initial text writer

Author: einarf

demosys/text/__init__.py

@@ -1,8 +1,10 @@
 import os
 from demosys.conf import settings
 
-from .writer_2d import TextWriter2D  # noqa
-from .renderer_2d import TextRenderer2D  # noqa
+from .writer2d import TextWriter2D  # noqa
+from .renderer2d import TextRenderer2D  # noqa
 
-
-settings.add_shader_dir(os.path.join(os.path.dirname(__file__), 'shaders'))
+# Register resource paths
+settings.add_shader_dir(os.path.join(os.path.dirname(__file__), 'resources', 'shaders'))
+settings.add_texture_dir(os.path.join(os.path.dirname(__file__), 'resources', 'textures'))
+settings.add_data_dir(os.path.join(os.path.dirname(__file__), 'resources', 'data'))

demosys/text/base.py

@@ -1,6 +1,8 @@
 """
 Text writer using monospace font from texture
 """
+import json
+
 from demosys import context
 
 
@@ -11,6 +13,41 @@ class BaseText:
 
     def __init__(self):
         self.ctx = context.ctx()
+        self._meta = None
+        self._ct = None
 
     def draw(self, *args, **kwargs):
         raise NotImplementedError()
+
+    def _translate_data(self, data):
+        """Translate character bytes into texture positions"""
+        return [self._meta.characters - 1 - self._ct[c] for c in data]
+
+    def _init(self, meta: 'Meta'):
+        self._meta = meta
+        # Check if the atlas size is sane
+        if not self._meta.characters * self._meta.character_height == self._meta.atlas_height:
+            raise ValueError("characters * character_width != atlas_height")
+
+        self._generate_character_map()
+
+    def _generate_character_map(self):
+        """Generate character translation map (latin1 pos to texture pos)"""
+        self._ct = [-1] * 256
+        index = 0
+        for crange in self._meta.character_ranges:
+            for cpos in range(crange['min'], crange['max'] + 1):
+                self._ct[cpos] = index
+                index += 1
+
+
+class Meta:
+    """Font metadata"""
+    def __init__(self, meta):
+        self._meta = json.loads(meta)
+        self.characters = self._meta['characters']
+        self.character_ranges = self._meta['character_ranges']
+        self.character_height = self._meta['character_height']
+        self.character_width = self._meta['character_width']
+        self.atlas_height = self._meta['atlas_height']
+        self.atlas_width = self._meta['atlas_width']

demosys/text/renderer_2d.py demosys/text/renderer2d.pydemosys/text/renderer_2d.py renamed to demosys/text/renderer2d.py

@@ -1,3 +1,4 @@
+from demosys.resources import shaders
 from .base import BaseText
 
 
@@ -11,11 +12,12 @@ def __init__(self, area, size=0.1, text=""):
         """
         super().__init__(text)
         self.area = area
+        self.size = size
         self._text = text
 
         self.fbo = None
         self.vao = None
-        self.shader = None
+        self.shader = shaders.get('demosys/text/textwriter.glsl', create=True)
 
     @property
     def text(self):

demosys/text/resources/data/demosys/text/meta.json

@@ -0,0 +1,17 @@
+{
+  "characters": 190,
+  "character_ranges": [
+    {
+      "min": 32,
+      "max": 126
+    },
+    {
+      "min": 161,
+      "max": 255
+    }
+  ],
+  "character_height": 159,
+  "character_width": 77,
+  "atlas_height": 30210,
+  "atlas_width": 77
+}

…ext/shaders/demosys/text/textwriter.glsl …ces/shaders/demosys/text/textwriter.glsldemosys/text/shaders/demosys/text/textwriter.glsl renamed to demosys/text/resources/shaders/demosys/text/textwriter.glsl demosys/text/shaders/demosys/text/textwriter.glsl renamed to demosys/text/resources/shaders/demosys/text/textwriter.glsl

@@ -0,0 +1,59 @@
+import numpy
+import moderngl
+from demosys.opengl import VAO
+from demosys.resources import data, shaders, textures
+from demosys.opengl import TextureArray
+
+from .base import BaseText, Meta
+
+
+class TextWriter2D(BaseText):
+
+    def __init__(self, area, size=0.1, text=""):
+        """
+        :param area: (x, y) Text area size (number of characters)
+        :param size: Text size
+        :param text: Initial text
+        """
+        super().__init__()
+        self.area = area
+        self.size = size
+        self._text = text.encode('latin1')
+
+        self._vao = None
+        self._texture = textures.get('demosys/text/VeraMono.png', cls=TextureArray, layers=190, create=True)
+        self._shader = shaders.get('demosys/text/textwriter.glsl', create=True)
+        self._config = data.get('demosys/text/meta.json', create=True)
+
+        data.on_loaded(self._post_load)
+
+    def _post_load(self):
+        """Parse font metadata after resources are loaded"""
+        self._init(Meta(self._config.data))
+
+        self._string_data = self._translate_data(self._text)
+        self._string_buffer = self.ctx.buffer(
+            data=numpy.array(self._string_data, dtype=numpy.uint32).tobytes()
+        )
+        self._pos = self.ctx.buffer(data=bytes([0] * 4 * 3))
+
+        self._vao = VAO("textwriter", mode=moderngl.POINTS)
+        self._vao.buffer(self._pos, '3f', 'in_position')
+        self._vao.buffer(self._string_buffer, '1u', 'in_char_id', per_instance=True)
+
+    @property
+    def text(self):
+        return self._text
+
+    @text.setter
+    def text(self, value):
+        self._text = value
+
+    def draw(self, proj_matrix, view_matrix):
+        # print(self._text, self._string_data)
+        self._texture.use(location=0)
+        self._shader.uniform("m_proj", proj_matrix.astype('f4').tobytes())
+        self._shader.uniform("m_mv", view_matrix.astype('f4').tobytes())
+        self._shader.uniform("font_texture", 0)
+        self._shader.uniform("char_size", (self._meta.character_width / self._meta.character_height, 1.0))
+        self._vao.draw(self._shader, instances=len(self._string_data))

demosys/text/resources/textures/demosys/text/VeraMono.png

@@ -1,12 +1,23 @@
+import moderngl
 from demosys.effects import effect
 from demosys.text import TextWriter2D
+from pyrr import matrix44
 
 
 class TextEffect(effect.Effect):
 
     def __init__(self):
-        self.writer = TextWriter2D((10, 1), text="Hello world!")
+        super().__init__()
+        self.writer = TextWriter2D((10, 1),
+            text="Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world! Hello world!")
+
+    def post_load(self):
+        pass
 
     @effect.bind_target
     def draw(self, time, frametime, target):
-        self.writer.draw()
+        self.ctx.disable(moderngl.CULL_FACE)
+        m_proj = self.create_projection()
+        # m_mv = matrix44.create_identity()
+
+        self.writer.draw(m_proj, self.sys_camera.view_matrix)