Render 3D Scene with Panorama Mode in Depth

Render 3D Scene with Panorama Mode in Depth

In this article, we create a Camera and two Light objects to capture the scene, the ShaderSet class helps to create depth shader.

Programming Sample

This code example renders 3D scene with Panorama mode in depth.

C#

 public static void Run()

{

    // The path to the documents directory.

    string dataDir = RunExamples.GetDataDir();

    //load the scene

    Scene scene = new Scene(dataDir + "skybox.obj");

    //create a camera for capturing the cube map

    Camera cam = new Camera(ProjectionType.Perspective);

    cam.NearPlane = 0.1;

    cam.FarPlane = 200;

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

    cam.RotationMode = RotationMode.FixedDirection;

    //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()

    {

        LightType = LightType.Point,

        ConstantAttenuation = 0.1,

        Color = new Vector3(Color.CadetBlue)

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

    //create a render target

    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 * 3, 1024);

        //a viewport is required on the render target

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

        renderer.ShaderSet = CreateDepthShader(renderer);

        renderer.Render(rt);

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

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

        equirectangular.Input = rt.Targets[0];

        renderer.Execute(equirectangular, final);

        //save the texture into disk

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

    }

}

private static ShaderSet CreateDepthShader(Renderer renderer)

{

    GLSLSource src = new GLSLSource();

    src.VertexShader = @"#version 330 core

    layout (location = 0) in vec3 position;

    uniform mat4 matWorldViewProj;

    out float depth;

    void main()

    {

        gl_Position = matWorldViewProj * vec4(position, 1.0f);

        float zfar = 200.0;

        float znear = 0.5;

        //visualize the depth by linearize it so we don't get a blank screen

        depth = (2.0 * znear) / (zfar + znear - gl_Position.z /gl_Position.w  * (zfar - znear));

    }";

    src.FragmentShader = @"#version 330 core

    in float depth;

    out vec4 color;

    void main()

    {

        color = vec4(depth, depth, depth, 1);

    }";

    //we only need the position to render the depth map

    VertexDeclaration fd = new VertexDeclaration();

    fd.AddField(VertexFieldDataType.FVector3, VertexFieldSemantic.Position);

    //compile shader from GLSL source code and specify the vertex input format

    var shader = renderer.RenderFactory.CreateShaderProgram(src, fd);

    //connect GLSL uniform to renderer's internal variable

    shader.Variables = new ShaderVariable[]

    {

        new ShaderVariable("matWorldViewProj", VariableSemantic.MatrixWorldViewProj)

    };

    //create a shader set

    ShaderSet ret = new ShaderSet();

    //we only use the fallback, and left other shaders unassigned, so all materials will be rendered by this shader

    ret.Fallback = shader;

    return ret;

}