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OpenGL OpenTK Skybox texture not showing

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Hello, I'm trying to create a skybox in OpenGL I managed to draw the cube and change its color but i am not able to bind the texture to the cubemap or to bind the cubemap into the skybox. Below is some of my code in C# (i am using a binding):


The CubeMap class

public class CubeMap
        public uint ID;
        Image Source;
        public CubeMap(string source){
            Source = new Bitmap(source);
            List<Bitmap> Faces = new List<Bitmap>();
            Bitmap NewBmp = new Bitmap(128,128);
            using(Graphics G = Graphics.FromImage(NewBmp)){
                G.DrawImage(Source,0,0, new Rectangle(384,128,128,128),GraphicsUnit.Pixel);
                Faces.Add((Bitmap) NewBmp.Clone());//right
                G.DrawImage(Source,0,0, new Rectangle(0,128,128,128),GraphicsUnit.Pixel);
                Faces.Add((Bitmap) NewBmp.Clone());//left
                G.DrawImage(Source,0,0, new Rectangle(0,0,128,128),GraphicsUnit.Pixel);
                Faces.Add((Bitmap) NewBmp.Clone());//top
                G.DrawImage(Source,0,0, new Rectangle(0,256,128,128),GraphicsUnit.Pixel);
                Faces.Add((Bitmap) NewBmp.Clone());
                G.DrawImage(Source,0,0, new Rectangle(512,128,128,128),GraphicsUnit.Pixel);
                Faces.Add((Bitmap) NewBmp.Clone());
                G.DrawImage(Source,0,0, new Rectangle(128,128,128,128),GraphicsUnit.Pixel);
                Faces.Add((Bitmap) NewBmp.Clone());
            GL.GenTextures(1, out ID);
            GL.BindTexture(TextureTarget.TextureCubeMap, ID);
            for(int i = 0; i<Faces.Count; i++){
                System.Drawing.Imaging.BitmapData data = Faces[i].LockBits(new Rectangle(0,0,Faces[i].Width, Faces[i].Height), System.Drawing.Imaging.ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
                GL.TexImage2D(TextureTarget.TextureCubeMapPositiveX+i, 0, PixelInternalFormat.Rgb, data.Width, data.Height,0, PixelFormat.Rgb, PixelType.UnsignedByte, data.Scan0);
            GL.TexParameter(TextureTarget.TextureCubeMap, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
            GL.TexParameter(TextureTarget.TextureCubeMap, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
            GL.TexParameter(TextureTarget.TextureCubeMap, TextureParameterName.TextureWrapS, (int) TextureWrapMode.ClampToEdge);
            GL.TexParameter(TextureTarget.TextureCubeMap, TextureParameterName.TextureWrapT, (int) TextureWrapMode.ClampToEdge);
            GL.TexParameter(TextureTarget.TextureCubeMap, TextureParameterName.TextureWrapR, (int) TextureWrapMode.ClampToEdge);
            GL.BindTexture(TextureTarget.TextureCubeMap, 0);

Here I bind the cubemap to the shader


GL.Uniform1(GL.GetUniformLocation(SkyboxShader.ShaderID, "skybox"), 0);
GL.BindTexture(TextureTarget.TextureCubeMap, Box.ID);//Box is an object of type cubemap             
GL.BindBuffer(BufferTarget.ArrayBuffer, BufferID);
GL.DrawArrays(PrimitiveType.Triangles, 0, 36);

Vertex Shader

#version 120
attribute vec3 position;
varying vec3 TexCoords;

void main()
gl_Position = vec4(position, 1.0);
TexCoords = position;

Fragment Shader

#version 120
varying vec3 TexCoords;

uniform samplerCube skybox;

void main()
    gl_FragColor = textureCube(skybox, TexCoords);

OpenGL did not throw any errors, and a black box is being rendered instead of the skybox.

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