v1.4.0

Added

• Added BufferManager to handle buffer data for all the scene objects.
• Added make_texture_buffer in gl.py for matrix and settings array.

Changed

• Greatly improved performance for scenes with large number of objects.
• All scene objects are rendered once in a combined buffer through single draw call.
• Updated shaders to version OpenGL 330 Core Profile.
• Implemented matrix and settings array as texture buffer instead of uniforms to improve performance.
• Blending of transparent objects is handled in a second draw on top of the opaque objects.

Removed

• Removed all low-level buffer related functions from SceneObjects, which is now handled together by BufferManager.
• Removed redundant Shaders: grid_shader, instance_shader, surface_shader and arrow_shader.
• Removed paint_instance from Renderer as it handled by a shader flag.