GraphicsContext

The GraphicsContext is the central class for displaying your application. It's used to create and manage graphic resources.

Like the majority of Low-level-API classes, GraphicsContext is an abstract class that exposes the common functionality of each graphics API (e.g. DirectX, Vulkan, Metal...). To use this API, you just need to create or access the GraphicsContext instance, indicating the appropriate implementation depending on which graphic backend you are interested in.

In the following example, we are creating a DirectX11 GraphicsContext:

var graphicsContext = new Evergine.DirectX11.DX11GraphicsContext();

Use the specified constructor to initialize a concrete graphics API.

API	Class
DirectX 11	new DX11GraphicsContext()
DirectX 12	new DX12GraphicsContext()
Vulkan	new VKGraphicsContext()
OpenGL	new GLGraphicsContext()
Metal	new MTLGraphicsContext()

Initialize the Device

Once you have created the GraphicsContext, to create resources and render your content, you need to create the graphics device:

graphicsContext.CreateDevice();

Validation Layer

To enable debug graphics mode, you must add the ValidationLayer object to the device constructor. This will show you the native and internal errors:

// Add a ValidationLayer instance in the CreateDevice invocation...
graphicsContext.CreateDevice(new ValidationLayer());

By default, the ValidationLayer uses exceptions to notify any issue, but it is possible to change it:

Notify Method	Declaration	Description
Exception	new ValidationLayer()	Throws exceptions for each internal error and stops the execution.
Trace	new ValidationLayer(ValidationLayer.NotifyMethod.Trace)	Displays all errors in the console without stopping the execution.
Event	new ValidationLayer(ValidationLayer.NotifyMethod.Event)	The ValidationLayer.Error event allows you to obtain the error messages.

Initialize Swapchain

Once you have the GraphicsContext, you can use it to create the swapchain and render on a surface.

// Create a window...
var windowSystem = new Evergine.WindowsForms.FormsWindowsSystem();
var window = windowSystem.CreateWindow(windowTitle, width, height);

// Create a swapchain descriptor and assign the surface info...
var swapChainDescriptor = new SwapChainDescription()
{
    Width = window.Width,
    Height = window.Height,
    SurfaceInfo = info,
    ColorTargetFormat = PixelFormat.R8G8B8A8_UNorm,
    ColorTargetFlags = TextureFlags.RenderTarget | TextureFlags.ShaderResource,
    DepthStencilTargetFormat = PixelFormat.D24_UNorm_S8_UInt,
    DepthStencilTargetFlags = TextureFlags.DepthStencil,
    SampleCount = this.SampleCount,
    IsWindowed = true,
    RefreshRate = 60,
    SurfaceInfo = window.SurfaceInfo
};

// Finally, create the swapchain...
var swapChain = this.graphicsContext.CreateSwapChain(swapChainDescriptor);
swapChain.VerticalSync = false;

To create the surface, first, you need to select a UI technology:

UI	Class
Windows Forms	Evergine.Forms.FormsWindowsSystem
WPF	Evergine.WPF.WPFWindowsSystem
SDL	Evergine.SDL.SDLWindowsSystem
Android	Evergine.AndroidView.AndroidWindowsSystem
iOS	Evergine.iOSView.iOSWindowsSystem
UWP	Evergine.UWPView.UWPWindowsSystem
WinUI	Evergine.WinUI.WinUIWindowsSystem
MixedReality	Evergine.MixedReality.MixedRealityWindowsSystem
Web	Evergine.Web.WebWindowsSystem

Create from scratch

Visit the Low-Level test samples to learn how to create an application from scratch using this cross-platform API.