Source code for arcade.context

"""
Arcade's version of the OpenGL Context.
Contains pre-loaded programs
"""
from pathlib import Path
from typing import Dict, Optional, Tuple, Union
from contextlib import contextmanager

import pyglet
from pyglet import gl
from pyglet.graphics.shader import UniformBufferObject
from PIL import Image

import arcade
from arcade.gl import BufferDescription, Context
from arcade.gl.compute_shader import ComputeShader
from arcade.gl.program import Program
from arcade.gl.texture import Texture
from arcade.gl.vertex_array import Geometry
from pyglet.math import Mat4
from arcade.texture_atlas import TextureAtlas


[docs]class ArcadeContext(Context): """ An OpenGL context implementation for Arcade with added custom features. This context is normally accessed thought :py:attr:`arcade.Window.ctx`. Pyglet users can use the base Context class and extend that as they please. **This is part of the low level rendering API in arcade and is mainly for more advanced usage** :param pyglet.window.Window window: The pyglet window :param str gc_mode: The garbage collection mode for opengl objects. ``auto`` is just what we would expect in python while ``context_gc`` (default) requires you to call ``Context.gc()``. The latter can be useful when using multiple threads when it's not clear what thread will gc the object. """ atlas_size = 512, 512 def __init__(self, window: pyglet.window.Window, gc_mode: str = "context_gc", gl_api: str = "gl"): super().__init__(window, gc_mode=gc_mode, gl_api=gl_api) # Enabled blending by default self.enable(self.BLEND) self.blend_func = self.BLEND_DEFAULT # Set up a default orthogonal projection for sprites and shapes self._window_block: UniformBufferObject = window.ubo self.bind_window_block() self.projection_2d = ( 0, self.screen.width, 0, self.screen.height, ) # --- Pre-load system shaders here --- # FIXME: These pre-created resources needs to be packaged nicely # Just having them globally in the context is probably not a good idea self.line_vertex_shader: Program = self.load_program( vertex_shader=":resources:shaders/shapes/line/line_vertex_shader_vs.glsl", fragment_shader=":resources:shaders/shapes/line/line_vertex_shader_fs.glsl", ) self.line_generic_with_colors_program: Program = self.load_program( vertex_shader=":resources:shaders/shapes/line/line_generic_with_colors_vs.glsl", fragment_shader=":resources:shaders/shapes/line/line_generic_with_colors_fs.glsl", ) self.shape_element_list_program: Program = self.load_program( vertex_shader=":resources:shaders/shape_element_list_vs.glsl", fragment_shader=":resources:shaders/shape_element_list_fs.glsl", ) # self.sprite_list_program = self.load_program( # vertex_shader=':resources:shaders/sprites/sprite_list_instanced_vs.glsl', # fragment_shader=':resources:shaders/sprites/sprite_list_instanced_fs.glsl', # ) self.sprite_list_program_no_cull: Program = self.load_program( vertex_shader=":resources:shaders/sprites/sprite_list_geometry_vs.glsl", geometry_shader=":resources:shaders/sprites/sprite_list_geometry_no_cull_geo.glsl", fragment_shader=":resources:shaders/sprites/sprite_list_geometry_fs.glsl", ) self.sprite_list_program_no_cull["sprite_texture"] = 0 self.sprite_list_program_no_cull["uv_texture"] = 1 self.sprite_list_program_cull: Program = self.load_program( vertex_shader=":resources:shaders/sprites/sprite_list_geometry_vs.glsl", geometry_shader=":resources:shaders/sprites/sprite_list_geometry_cull_geo.glsl", fragment_shader=":resources:shaders/sprites/sprite_list_geometry_fs.glsl", ) self.sprite_list_program_cull["sprite_texture"] = 0 self.sprite_list_program_cull["uv_texture"] = 1 # Shapes self.shape_line_program: Program = self.load_program( vertex_shader=":resources:/shaders/shapes/line/unbuffered_vs.glsl", fragment_shader=":resources:/shaders/shapes/line/unbuffered_fs.glsl", geometry_shader=":resources:/shaders/shapes/line/unbuffered_geo.glsl", ) self.shape_ellipse_filled_unbuffered_program: Program = self.load_program( vertex_shader=":resources:/shaders/shapes/ellipse/filled_unbuffered_vs.glsl", fragment_shader=":resources:/shaders/shapes/ellipse/filled_unbuffered_fs.glsl", geometry_shader=":resources:/shaders/shapes/ellipse/filled_unbuffered_geo.glsl", ) self.shape_ellipse_outline_unbuffered_program: Program = self.load_program( vertex_shader=":resources:/shaders/shapes/ellipse/outline_unbuffered_vs.glsl", fragment_shader=":resources:/shaders/shapes/ellipse/outline_unbuffered_fs.glsl", geometry_shader=":resources:/shaders/shapes/ellipse/outline_unbuffered_geo.glsl", ) self.shape_rectangle_filled_unbuffered_program = self.load_program( vertex_shader=":resources:/shaders/shapes/rectangle/filled_unbuffered_vs.glsl", fragment_shader=":resources:/shaders/shapes/rectangle/filled_unbuffered_fs.glsl", geometry_shader=":resources:/shaders/shapes/rectangle/filled_unbuffered_geo.glsl", ) self.atlas_resize_program: Program = self.load_program( vertex_shader=":resources:/shaders/atlas/resize_vs.glsl", geometry_shader=":resources:/shaders/atlas/resize_gs.glsl", fragment_shader=":resources:/shaders/atlas/resize_fs.glsl", ) self.atlas_resize_program["atlas_old"] = 0 # Configure texture channels self.atlas_resize_program["atlas_new"] = 1 self.atlas_resize_program["texcoords_old"] = 2 self.atlas_resize_program["texcoords_new"] = 3 # SpriteList collision resources self.collision_detection_program = self.load_program( vertex_shader=":resources:shaders/collision/col_trans_vs.glsl", geometry_shader=":resources:shaders/collision/col_trans_gs.glsl", ) self.collision_buffer = self.buffer(reserve=1024 * 4) self.collision_query = self.query(samples=False, time=False, primitives=True) # --- Pre-created geometry and buffers for unbuffered draw calls ---- # FIXME: These pre-created resources needs to be packaged nicely # Just having them globally in the context is probably not a good idea self.generic_draw_line_strip_color = self.buffer(reserve=4 * 1000) self.generic_draw_line_strip_vbo = self.buffer(reserve=8 * 1000) self.generic_draw_line_strip_geometry = self.geometry( [ BufferDescription(self.generic_draw_line_strip_vbo, "2f", ["in_vert"]), BufferDescription( self.generic_draw_line_strip_color, "4f1", ["in_color"], normalized=["in_color"], ), ] ) # Shape line(s) # Reserve space for 1000 lines (2f pos, 4f color) # TODO: Different version for buffered and unbuffered # TODO: Make round-robin buffers self.shape_line_buffer_pos = self.buffer(reserve=8 * 10) # self.shape_line_buffer_color = self.buffer(reserve=4 * 10) self.shape_line_geometry = self.geometry( [ BufferDescription(self.shape_line_buffer_pos, "2f", ["in_vert"]), # BufferDescription(self.shape_line_buffer_color, '4f1', ['in_color'], normalized=['in_color']) ] ) # ellipse/circle filled self.shape_ellipse_unbuffered_buffer = self.buffer(reserve=8) self.shape_ellipse_unbuffered_geometry: Geometry = self.geometry( [BufferDescription(self.shape_ellipse_unbuffered_buffer, "2f", ["in_vert"])] ) # ellipse/circle outline self.shape_ellipse_outline_unbuffered_buffer = self.buffer(reserve=8) self.shape_ellipse_outline_unbuffered_geometry: Geometry = self.geometry( [ BufferDescription( self.shape_ellipse_outline_unbuffered_buffer, "2f", ["in_vert"] ) ] ) # rectangle filled self.shape_rectangle_filled_unbuffered_buffer = self.buffer(reserve=8) self.shape_rectangle_filled_unbuffered_geometry: Geometry = self.geometry( [ BufferDescription( self.shape_rectangle_filled_unbuffered_buffer, "2f", ["in_vert"] ) ] ) self.atlas_geometry: Geometry = self.geometry() self._atlas: Optional[TextureAtlas] = None # Global labels we modify in `arcade.draw_text`. # These multiple labels with different configurations are stored self.pyglet_label_cache: Dict[str, pyglet.text.Label] = {} # self.active_program = None self.point_size = 1.0
[docs] def reset(self) -> None: """ Reset context flags and other states. This is mostly used in unit testing. """ self.screen.use(force=True) self.bind_window_block() # self.active_program = None arcade.set_viewport(0, self.window.width, 0, self.window.height) self.enable_only(self.BLEND) self.blend_func = self.BLEND_DEFAULT self.point_size = 1.0
[docs] def bind_window_block(self) -> None: """ Binds the projection and view uniform buffer object. This should always be bound to index 0 so all shaders have access to them. """ gl.glBindBufferRange( gl.GL_UNIFORM_BUFFER, 0, self._window_block.buffer.id, 0, 128, # 32 x 32bit floats (two mat4) )
@property def default_atlas(self) -> TextureAtlas: """ The default texture atlas. This is created when arcade is initialized. All sprite lists will use use this atlas unless a different atlas is passed in the :py:class:`arcade.SpriteList` constructor. :type: TextureAtlas """ if not self._atlas: # Create the default texture atlas # 8192 is a safe maximum size for textures in OpenGL 3.3 # We might want to query the max limit, but this makes it consistent # across all OpenGL implementations. self._atlas = TextureAtlas( self.atlas_size, border=1, auto_resize=True, ctx=self, ) return self._atlas @property def projection_2d(self) -> Tuple[float, float, float, float]: """Get or set the global orthogonal projection for arcade. This projection is used by sprites and shapes and is represented by four floats: ``(left, right, bottom, top)`` :type: Tuple[float, float, float, float] """ return self._projection_2d @projection_2d.setter def projection_2d(self, value: Tuple[float, float, float, float]): if not isinstance(value, tuple) or len(value) != 4: raise ValueError( f"projection must be a 4-component tuple, not {type(value)}: {value}" ) self._projection_2d = value self._projection_2d_matrix = Mat4.orthogonal_projection( value[0], value[1], value[2], value[3], -100, 100, ) self.window.projection = self._projection_2d_matrix @property def projection_2d_matrix(self) -> Mat4: """ Get the current projection matrix. This 4x4 float32 matrix is calculated when setting :py:attr:`~arcade.ArcadeContext.projection_2d`. :type: pyglet.math.Mat4 """ return self._projection_2d_matrix @projection_2d_matrix.setter def projection_2d_matrix(self, value: Mat4): if not isinstance(value, Mat4): raise ValueError("projection_matrix must be a Mat4 object") self._projection_2d_matrix = value self.window.projection = self._projection_2d_matrix
[docs] @contextmanager def pyglet_rendering(self): """ Context manager for doing redering with pyglet ensuring context states are reverted. This affects things like blending. """ blend_enabled = self.is_enabled(self.BLEND) try: yield finally: if blend_enabled: self.enable(self.BLEND)
[docs] def load_program( self, *, vertex_shader: Union[str, Path], fragment_shader: Union[str, Path] = None, geometry_shader: Union[str, Path] = None, tess_control_shader: Union[str, Path] = None, tess_evaluation_shader: Union[str, Path] = None, defines: dict = None, ) -> Program: """Create a new program given a file names that contain the vertex shader and fragment shader. Note that fragment and geometry shader are optional for when transform shaders are loaded. This method also supports the ``:resources:`` prefix. It's recommended to use absolute paths, but not required. Example:: # The most common use case if having a vertex and fragment shader program = window.ctx.load_program( vertex_shader="vert.glsl", fragment_shader="frag.glsl", ) :param Union[str,pathlib.Path] vertex_shader: path to vertex shader :param Union[str,pathlib.Path] fragment_shader: path to fragment shader (optional) :param Union[str,pathlib.Path] geometry_shader: path to geometry shader (optional) :param dict defines: Substitute ``#define`` values in the source :param Union[str,pathlib.Path] tess_control_shader: Tessellation Control Shader :param Union[str,pathlib.Path] tess_evaluation_shader: Tessellation Evaluation Shader """ from arcade.resources import resolve_resource_path vertex_shader_src = resolve_resource_path(vertex_shader).read_text() fragment_shader_src = None geometry_shader_src = None tess_control_src = None tess_evaluation_src = None if fragment_shader: fragment_shader_src = resolve_resource_path(fragment_shader).read_text() if geometry_shader: geometry_shader_src = resolve_resource_path(geometry_shader).read_text() if tess_control_shader and tess_evaluation_shader: tess_control_src = resolve_resource_path(tess_control_shader).read_text() tess_evaluation_src = resolve_resource_path( tess_evaluation_shader ).read_text() return self.program( vertex_shader=vertex_shader_src, fragment_shader=fragment_shader_src, geometry_shader=geometry_shader_src, tess_control_shader=tess_control_src, tess_evaluation_shader=tess_evaluation_src, defines=defines, )
[docs] def load_compute_shader(self, path: Union[str, Path]) -> ComputeShader: """ Loads a compute shader from file. This methods supports resource handles. Example:: ctx.load_compute_shader(":shader:compute/do_work.glsl") :param Union[str,pathlib.Path] path: Path to texture """ from arcade.resources import resolve_resource_path path = resolve_resource_path(path) return self.compute_shader(source=path.read_text())
[docs] def load_texture( self, path: Union[str, Path], *, flip: bool = True, build_mipmaps: bool = False, ) -> Texture: """ Loads and creates an OpenGL 2D texture. Currently all textures are converted to RGBA for simplicity. Example:: # Load a texture in current working directory texture = window.ctx.load_texture("background.png") # Load a texture using Arcade resource handle texture = window.ctx.load_texture(":textures:background.png") :param Union[str,pathlib.Path] path: Path to texture :param bool flip: Flips the image upside down :param bool build_mipmaps: Build mipmaps for the texture """ from arcade.resources import resolve_resource_path path = resolve_resource_path(path) image = Image.open(str(path)) if flip: image = image.transpose(Image.FLIP_TOP_BOTTOM) texture = self.texture( image.size, components=4, data=image.convert("RGBA").tobytes() ) image.close() if build_mipmaps: texture.build_mipmaps() return texture