from typing import Union
import logging
import moderngl
from moderngl_window.loaders.base import BaseLoader
from moderngl_window.opengl import program
from moderngl_window.exceptions import ImproperlyConfigured
logger = logging.getLogger(__name__)
class Loader(BaseLoader):
kind = "separate"
[docs]
def load(
self,
) -> Union[moderngl.Program, moderngl.ComputeShader, program.ReloadableProgram]:
"""Loads a shader program were each shader is a separate file.
This detected and dictated by the ``kind`` in the ``ProgramDescription``.
Returns:
moderngl.Program: The Program instance
"""
prog = None
vs_source = self._load_shader("vertex", self.meta.vertex_shader)
geo_source = self._load_shader("geometry", self.meta.geometry_shader)
fs_source = self._load_shader("fragment", self.meta.fragment_shader)
tc_source = self._load_shader("tess_control", self.meta.tess_control_shader)
te_source = self._load_shader(
"tess_evaluation", self.meta.tess_evaluation_shader
)
cs_source = self._load_shader("compute", self.meta.compute_shader)
if vs_source:
shaders = program.ProgramShaders.from_separate(
self.meta,
vs_source,
geometry_source=geo_source,
fragment_source=fs_source,
tess_control_source=tc_source,
tess_evaluation_source=te_source,
)
shaders.handle_includes(self._load_source)
prog = shaders.create()
# Wrap the program if reloadable is set
if self.meta.reloadable:
# Disable reload flag so reloads will return Program instances
self.meta.reloadable = False
# Wrap it ..
prog = program.ReloadableProgram(self.meta, prog)
elif cs_source:
shaders = program.ProgramShaders.compute_shader(self.meta, cs_source)
shaders.handle_includes(self._load_source)
prog = shaders.create_compute_shader()
else:
raise ImproperlyConfigured("Cannot find a shader source to load")
return prog
def _load_shader(self, shader_type: str, path: str):
"""Load a single shader source"""
if path:
resolved_path = self.find_program(path)
if not resolved_path:
raise ImproperlyConfigured(
"Cannot find {} shader '{}'".format(shader_type, path)
)
logger.info("Loading: %s", resolved_path)
with open(str(resolved_path), "r") as fd:
return fd.read()
def _load_source(self, path):
"""Finds and loads a single source file.
Args:
path: Path to resource
Returns:
Tuple[resolved_path, source]: The resolved path and the source
"""
resolved_path = self.find_program(path)
if not resolved_path:
raise ImproperlyConfigured("Cannot find program '{}'".format(path))
logger.info("Loading: %s", path)
with open(str(resolved_path), "r") as fd:
return resolved_path, fd.read()