RenderList.DrawNow

void DrawNow(Tex toRenderTarget, Matrix camera, Matrix projection, Color clearColor, RenderClear clear, Rect viewportPct, RenderLayer layerFilter)

Draws the RenderList to a rendertarget texture immediately. It does not clear the list.


Tex toRenderTarget	The rendertarget texture to draw to.
Matrix camera	A TRS matrix representing the location and orientation of the camera. This matrix gets inverted later on, so no need to do it yourself.
Matrix projection	The projection matrix describes how the geometry is flattened onto the draw surface. Normally, you’d use Matrix.Perspective, and occasionally Matrix.Orthographic might be helpful as well.
Color clearColor	If the `clear` parameter is set to clear the color of `toRenderTarget`, then this is the color it will clear to. `default` would be a transparent black.
RenderClear clear	Describes if and how the rendertarget should be cleared before rendering. Note that clearing the target is unaffected by the viewport, so this will clean the entire surface!
Rect viewportPct	Allows you to specify a region of the rendertarget to draw to! This is in normalized coordinates, 0-1. If the width of this value is zero, then this will render to the entire texture.
RenderLayer layerFilter	This is a bit flag that allows you to change which layers StereoKit renders for this particular render viewpoint. To change what layers a visual is on, use a Draw method that includes a RenderLayer as a parameter.

Examples

Render Icon From a Model

UI with a custom rendererd icon

One place where RenderList excels, is at rendering icons or previews of Models or scenes! This snippet of code will take a Model asset, and render a preview of it into a small Sprite.

static Sprite MakeIcon(Model model, int resolution)
{
	RenderList list   = new RenderList();
	Tex        result = Tex.RenderTarget(resolution, resolution, 8);

	// Calculate a standard size that will fill the icon to the edges,
	// based on the camera parameters we pass to DrawNow.
	float scale = 1/model.Bounds.dimensions.Length;

	list.Add(model, Matrix.TS(-model.Bounds.center*scale, scale), Color.White);

	// OpenGL renders upside-down to rendertargets, so this is a simple fix
	// for our case here, we just flip the camera upside down.
	Vec3 up = Backend.Graphics == BackendGraphics.D3D11
		?  Vec3.Up
		: -Vec3.Up;
	list.DrawNow(result,
		Matrix.LookAt(V.XYZ(0,0,-1), Vec3.Zero, up),
		Matrix.Perspective(45, 1, 0.01f, 10));

	// Clearing isn't _necessary_ here, but DrawNow does not clear the list
	// after drawing! This will free up assets that were referenced in the
	// list without waiting for GC to destroy the RenderList object.
	list.Clear();

	return Sprite.FromTex(result.Copy());
}

From there, it’s pretty easy to load a Model up, and draw it on a button in the UI.

Sprite icon;
public void Initialize()
{
	Model model = Model.FromFile("Watermelon.glb");
	// Model loading is async, so we want to make sure the Model is fully
	// loaded before comitting it to a Sprite!
	Assets.BlockForPriority(int.MaxValue);
	icon = MakeIcon(model, 128);
}

Pose windowPose = new Pose(0,0,-0.5f, Quat.LookDir(0,0,1));
void ShowWindow()
{
	UI.WindowBegin("RenderList Icons", ref windowPose);
	UI.ButtonImg("Icon", icon, UIBtnLayout.CenterNoText, V.XX(UI.LineHeight*2));
	UI.WindowEnd();
}

Found an issue with these docs, or have some additional questions? Create an Issue on Github!