c# - OpenGL-如何创建和绑定(bind)立方体贴图数组？

超出纹理单位限制后，我决定使用立方体贴图数组纹理。

为了进行测试，我将立方体贴图的内容渲染为天空盒。事实是，当我绑定一个立方体贴图数组时，OpenGL会忽略，而是使用先前绑定的立方体贴图渲染天空盒。

GL.BindTexture(TextureTarget.TextureCubeMap, shadowMaps[5].cubeMapTexture);
GL.BindTexture(TextureTarget.TextureCubeMapArray, shadowMapArray.cubeMapHandle); // Ignored

我假设这是错误创建的立方体贴图数组的默认行为。据我所知，我已经正确完成了所有操作：Framebuffer complete。

那么，创建和绑定立方体贴图数组的正确方法是什么？

public class CubeMapArray
{
    public static int size = 512;
    public static int layers = 8; // number of cube maps in array

    public int FBO_handle;
    public int cubeMapHandle;
    public int cubeMapDepthHandle;

    // Constructor //
    public CubeMapArray()
    {
        // Create the FBO
        GL.GenFramebuffers(1, out FBO_handle);

        // Create and bind the CubeMap array
        GL.GenTextures(1, out cubeMapHandle);
        GL.BindTexture(TextureTarget.TextureCubeMapArray, cubeMapHandle);

        // Allocate storage space
        GL.TexImage3D(TextureTarget.TextureCubeMapArray, 0, PixelInternalFormat.Rg16, size, size, layers * 6, 0, PixelFormat.Red, PixelType.Float, IntPtr.Zero);

        // Set the suitable texture parameters
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Linear);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureWrapS, (int)TextureWrapMode.ClampToEdge);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureWrapT, (int)TextureWrapMode.ClampToEdge);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureWrapR, (int)TextureWrapMode.ClampToEdge);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureBaseLevel, 0);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureMaxLevel, 0);

        // Create and bind the CubeMap depth array
        GL.GenTextures(1, out cubeMapDepthHandle);
        GL.BindTexture(TextureTarget.TextureCubeMapArray, cubeMapDepthHandle);

        // Allocate storage space
        GL.TexImage3D(TextureTarget.TextureCubeMapArray, 0, PixelInternalFormat.DepthComponent, size, size, layers * 6, 0, PixelFormat.DepthComponent, PixelType.UnsignedByte, IntPtr.Zero);

        // Set the suitable texture parameters
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Linear);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureWrapS, (int)TextureWrapMode.ClampToEdge);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureWrapT, (int)TextureWrapMode.ClampToEdge);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureWrapR, (int)TextureWrapMode.ClampToEdge);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureBaseLevel, 0);
        GL.TexParameter(TextureTarget.TextureCubeMapArray, TextureParameterName.TextureMaxLevel, 0);

        // Attach cubemap texture as the FBO's color buffer
        GL.BindFramebuffer(FramebufferTarget.Framebuffer, FBO_handle);
        GL.FramebufferTexture(FramebufferTarget.Framebuffer, FramebufferAttachment.ColorAttachment0, cubeMapHandle, 0);
        GL.FramebufferTexture(FramebufferTarget.Framebuffer, FramebufferAttachment.DepthAttachment, cubeMapDepthHandle, 0);

        // Error check
        var errorcheck = GL.CheckFramebufferStatus(FramebufferTarget.Framebuffer);
        Console.WriteLine("CUBEMAP ARRAY: " + errorcheck);

        // Bind default framebuffer
        GL.BindFramebuffer(FramebufferTarget.Framebuffer, 0);
    }
}

}

着色器非常简单，令人惊讶的是，它可以绑定常规的立方体贴图。

顶点

#version 330

in vec3 texCoord;
out vec4 fragColor;
uniform samplerCube cubeMapArray[16];

void main (void)
{
    fragColor = texture(cubeMapArray[0], texCoord);
}

分段

#version 330

uniform mat4 modelMatrix;
uniform mat4 viewMatrix;
uniform mat4 projectionMatrix;

in vec3 in_position;
out vec3 texCoord;

void main()
{
    gl_Position = projectionMatrix * viewMatrix * modelMatrix * vec4(in_position, 1.0);
    texCoord = in_position;
}

最佳答案

您需要在着色器代码中使用相应的采样器类型。多维数据集映射数组在OpenGL 4.0和更高版本中可用，因此您还需要将GLSL版本增加到400或更高版本。

然后，着色器代码将遵循以下内容：

#version 400
...
uniform samplerCubeArray cubeMapArray;
...
fragColor = texture(cubeMapArray, vec4(texCoord, 0));

注意，用于采样的数组层被指定为纹理坐标的第四部分。