OrthographicCamera

Represents a camera that uses orthographic projection.

In this projection mode, an object's size in the rendered image stays constant regardless of its distance from the camera. This can be useful for rendering 2D scenes and UI elements, amongst other things.

Although multiple cameras can be added to the scene graph and inherit transformations from their parent objects, only one camera can be active at a time. The active camera is managed by the application’s runtime object:

cpp

class MyApp : public vglx::Application {
public:
  auto Configure() -> void override {}

  auto Setup() -> void override {
    SetCamera(
      vglx::OrthographicCamera::Create({
        .left = 0.0f,
        .right = 1024.0f,
        .top = 0.0f,
        .bottom = 768.0f,
        .near = 0.1f,
        .far = 100.0f
      })
    );
  }

  auto Update(float delta) -> bool override {
    return true;
  }
}

INFO

Derives from Camera and inherits all public properties and methods.

Construction

Constructors

OrthographicCamera()

Constructs an orthographic camera.

cpp

OrthographicCamera::OrthographicCamera(const Parameters& params);

Parameter	Description
params	Initialization parameters for constructing the camera.

Factories preferred

OrthographicCamera::Create() std::shared_ptr<OrthographicCamera>

Creates a shared instance of OrthographicCamera.

cpp

static std::shared_ptr<OrthographicCamera> OrthographicCamera::Create(const Parameters& params);

Parameter	Description
params	Initialization parameters for constructing the camera.

Types

OrthographicCamera::ResizePolicy enum

Defines how the orthographic projection should adapt on window resize.

Value	Description
PixelSpace	Projection matches framebuffer dimensions.
FixedVertical	Vertical extent remains constant, horizontal adjusted.
FixedHorizontal	Horizontal extent remains constant, vertical adjusted.

OrthographicCamera::Parameters struct

Parameters for constructing an OrthographicCamera object.

Parameter	Description
left float	Left clipping plane.
right float	Right clipping plane.
top float	Top clipping plane.
bottom float	Bottom clipping plane.
near float	Near clipping plane.
far float	Far clipping plane.

Properties

resize_policy ResizePolicy

The current resize policy for this camera.

cpp

ResizePolicy resize_policy {ResizePolicy::PixelSpace};

Functions

Resize() void virtual

Updates the projection transform to match the new viewport size.

The behavior depends on the current resize policy.

cpp

void OrthographicCamera::Resize(int width, int height) override;

Parameter	Description
width	Viewport width in pixels.
height	Viewport height in pixels.