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Base Mesh Class

BaseMesh

Bases: ABC

A base class for a mesh object that can be rendered in an OpenGL context.

Parameters:

Name Type Description Default
opengl_context Context

The OpenGL context.

 required
program Program

The shader program used to render the mesh.

 required
Source code in pynecraft/mesh/base.py 
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class BaseMesh(ABC):
    """A base class for a mesh object that can be rendered in an OpenGL context.

    Args:
        opengl_context (moderngl.Context): The OpenGL context.
        program (moderngl.Program): The shader program used to render the mesh.
    """

    def __init__(
        self, opengl_context: moderngl.Context, program: moderngl.Program
    ) -> None:
        super().__init__()
        self.opengl_context = opengl_context
        self.program = program
        self.vbo_format: str = None
        self.attributes: List[str] = None
        self.vertex_array_object: moderngl.VertexArray = None

    @abstractmethod
    def get_vertex_data(self) -> np.array:
        """Returns the vertex data for the mesh."""
        pass

    def get_vertex_array_object(self) -> moderngl.VertexArray:
        """Returns a VertexArray object for the mesh.

        Returns:
            moderngl.VertexArray: The VertexArray object.
        """
        vertex_data = self.get_vertex_data()

        # A vertex buffer object is an OpenGL object that stores vertex data
        # such as position, color, texture coordinates, and normals in GPU
        # memory, which is efficient for rendering because it minimizes the
        # data transfer between CPU and GPU.
        vertex_buffer_object = self.opengl_context.buffer(vertex_data)

        # A vertext array object is an OpenGL object that stores the format of
        # the vertex data as well as the method of extracting vertex data from
        # one or more vertex buffer objects. Essentially it stores the parameters
        # to interpret the vertex data structure.
        vertex_array_object = self.opengl_context.vertex_array(
            self.program,
            [(vertex_buffer_object, self.vbo_format, *self.attributes)],
            skip_errors=True,
        )

        return vertex_array_object

    def render(self):
        """Renders the mesh."""
        self.vertex_array_object.render()

get_vertex_array_object()

Returns a VertexArray object for the mesh.

Returns:

Type Description
VertexArray

moderngl.VertexArray: The VertexArray object.
Source code in pynecraft/mesh/base.py 
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def get_vertex_array_object(self) -> moderngl.VertexArray:
    """Returns a VertexArray object for the mesh.

    Returns:
        moderngl.VertexArray: The VertexArray object.
    """
    vertex_data = self.get_vertex_data()

    # A vertex buffer object is an OpenGL object that stores vertex data
    # such as position, color, texture coordinates, and normals in GPU
    # memory, which is efficient for rendering because it minimizes the
    # data transfer between CPU and GPU.
    vertex_buffer_object = self.opengl_context.buffer(vertex_data)

    # A vertext array object is an OpenGL object that stores the format of
    # the vertex data as well as the method of extracting vertex data from
    # one or more vertex buffer objects. Essentially it stores the parameters
    # to interpret the vertex data structure.
    vertex_array_object = self.opengl_context.vertex_array(
        self.program,
        [(vertex_buffer_object, self.vbo_format, *self.attributes)],
        skip_errors=True,
    )

    return vertex_array_object

get_vertex_data() abstractmethod

Returns the vertex data for the mesh.

Source code in pynecraft/mesh/base.py 
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@abstractmethod
def get_vertex_data(self) -> np.array:
    """Returns the vertex data for the mesh."""
    pass

render()

Renders the mesh.

Source code in pynecraft/mesh/base.py 
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def render(self):
    """Renders the mesh."""
    self.vertex_array_object.render()