The Rendering Context

Top: Contents

A central object in Fermat is the RenderingContext, a class encapsulating all there is to know about a scene's to render, including:

• the camera,
• the framebuffer,
• the scene database, including lights, geometry and textures,
• the ray tracing context,
• some precomputed tables to help with material simulation and such,
• the actual renderer,

We'll now go through this list step by step.

The camera with which to render the current scene is specified by:

Camera& RenderingContext::get_camera()

The framebuffer and its attributes are specified by:

// get the frame buffer
//
FBufferStorage& RenderingContext::get_frame_buffer()

// get the target resolution
//
uint2 RenderingContext::get_res() const

// get the target aspect ratio
//
float RenderingContext::get_aspect_ratio() const

// get the target exposure
//
float RenderingContext::get_exposure() const

// get the target gamma
//
float RenderingContext::get_gamma() const

The mesh geometry is specified by:

// get a device-resident version of the scene's mesh
//
DeviceMeshStorage& RenderingContext::get_device_mesh()

// get a host-resident version of the scene's mesh
//
HostMeshStorage& RenderingContext::get_host_mesh()

The light sources are specified by:

// return the number of directional lights
//
uint32 RenderingContext::get_directional_lights_count() const

// return the host-side list of directional lights
//
const DirectionalLight* RenderingContext::get_host_directional_lights() const

// return the device-side list of directional lights
//
const DirectionalLight* RenderingContext::get_device_directional_lights() const

and:

// return the mesh emitters
//
MeshLightsStorage& RenderingContext::get_mesh_lights()

Notice that this is a host-side class holding the device-side storage needed to sample mesh emitters on the device. Its view is just a MeshLight, i.e. a class with the Light interface.

The ray tracing context is specified by:

// return the ray tracing context for the scene's geometry
//
RTContext& RenderingContext::get_rt_context()

Finally, Fermat allows plugins to register new renderers with the following call:

// register a new rendering interface type
//
uint32 register_renderer(const char* name, RendererFactoryFunction factory)

The factory is just a fuction/method returning a pointer to a new RendererInterface object:

typedef RendererInterface* (*RendererFactoryFunction)();

Next: The Renderer Interface