Create a Fish-eye lens effect on 3D scene and save in an image

Create a Fisheye lens effect

In this article, we create a Camera and two Light objects to capture the scene, also create a render target, create a viewport and execute the Fisheye projection post-processing with the cube map as input and finally save the Fisheye texture. The Execute method of Renderer class allows to execute the post processing effect and save the result to render target.

Programming Sample

This code example creates a Fisheye lens effect on 3D scene and save into the image format.

C#

 string path = @"D:\Projects\glTF-Sample-Models\1.0\VC\glTF-Binary\VC.glb";

//load the scene

Scene scene = new Scene(path);

//create a camera for capturing the cube map

Camera cam = new Camera(ProjectionType.Perspective)

{

    NearPlane = 0.1,

    FarPlane = 200,

    RotationMode = RotationMode.FixedDirection

};

scene.RootNode.CreateChildNode(cam).Transform.Translation = new Vector3(5, 6, 0);



//create two lights to illuminate the scene

scene.RootNode.CreateChildNode(new Light() {LightType = LightType.Point}).Transform.Translation = new Vector3(-10, 7, -10);

scene.RootNode.CreateChildNode(new Light()

{

    Color = new Vector3(Color.CadetBlue)

}).Transform.Translation = new Vector3(49, 0, 49);



//create a renderer

using (var renderer = Renderer.CreateRenderer())

{

    //Create a cube map render target with depth texture, depth is required when rendering a scene.

    IRenderTexture rt = renderer.RenderFactory.CreateCubeRenderTexture(new RenderParameters(false), 512, 512);

    //create a 2D texture render target with no depth texture used for image processing

    IRenderTexture final = renderer.RenderFactory.CreateRenderTexture(new RenderParameters(false, 32, 0, 0), 1024, 1024);



    //a viewport is required on the render target

    rt.CreateViewport(cam, RelativeRectangle.FromScale(0, 0, 1, 1));

    renderer.Render(rt);



    //execute the fisheye projection post-processing with the previous rendered cube map as input

    //the fisheye can have field of view more than 180 degree, so a cube map with all direction is required.

    PostProcessing fisheye = renderer.GetPostProcessing("fisheye");

    // we can change the fov to 360 instead of the default value 180.

    fisheye.FindProperty("fov").Value = 360.0;

    //Specify the cube map rendered from the scene as this post processing's input

    fisheye.Input = rt.Targets[0];

    //Execute the post processing effect and save the result to render target final

    renderer.Execute(fisheye, final);

    //save the texture into disk

    ((ITexture2D)final.Targets[0]).Save("fisheye.png", ImageFormat.Png);

}