Better Manual Rendering Handling

[ssell]

Currently, there is no good way of manually rendering a scene. Looking at ColorPicker as an example, one has to:

• Retrieve visible objects
• Retrieve camera matrices
• Sort objects
• Individually bind object uniforms
• Individually call object render methods

This sort of routine should only have to happen within a Renderer implementation. So a method needs to be added (most likely to SceneManager) to manually call a render. The following options should be available:

• Specify a camera (default all cameras)
• Specify a material override (default no material override)
• Renderer type (string, default to the active renderer)

Doing so will make certain effects much easier and uniform.

Example:

auto camera = OcularCameras->getMainCamera();
auto material = OcularResources->getResource<Material>("EffectA");

OcularScene->render(camera, material);