Python bgl.glReadPixels() Examples

The following are 1 code examples of bgl.glReadPixels(). You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may also want to check out all available functions/classes of the module bgl , or try the search function .
Example #1
Source File: opengl_utils.py    From Blender-Addon-Photogrammetry-Importer with MIT License 4 votes vote down vote up 
def render_opengl_image(image_name, cam, point_size):
    draw_manager = DrawManager.get_singleton()
    coords, colors = draw_manager.get_coords_and_colors()

    scene = bpy.context.scene
    render = bpy.context.scene.render

    width = render.resolution_x
    height = render.resolution_y
    # TODO Provide an option to render from the 3D view perspective
    # width = bpy.context.region.width
    # height = bpy.context.region.height

    offscreen = gpu.types.GPUOffScreen(width, height)
    with offscreen.bind():

        bgl.glPointSize(point_size)
        #bgl.glClear(bgl.GL_COLOR_BUFFER_BIT)
        #bgl.glClear(bgl.GL_DEPTH_BUFFER_BIT)

        view_matrix = cam.matrix_world.inverted()
        projection_matrix = cam.calc_matrix_camera(
            bpy.context.evaluated_depsgraph_get(), 
            x=width,
            y=height)
        perspective_matrix = projection_matrix @ view_matrix

        gpu.matrix.load_matrix(perspective_matrix)
        gpu.matrix.load_projection_matrix(Matrix.Identity(4))
        
        shader = gpu.shader.from_builtin('3D_FLAT_COLOR')
        shader.bind()
        batch = batch_for_shader(shader, "POINTS", {"pos": coords, "color": colors})
        batch.draw(shader)
        
        buffer = bgl.Buffer(bgl.GL_BYTE, width * height * 4)
        bgl.glReadPixels(0, 0, width, height, bgl.GL_RGBA, bgl.GL_UNSIGNED_BYTE, buffer)

    offscreen.free()

    image = create_image_lazy(image_name, width, height)
    copy_buffer_to_pixel(buffer, image)