c# - 如何调试 OpenTK？

Question

尝试制作游戏，但纹理从未出现在屏幕上。

只为四边形使用颜色是可行的，但是当我尝试为四边形添加纹理时，它只是显示为黑色方 block 。

基本片段着色器:

#version 300 es
precision highp float;

uniform sampler2D SS;

in vec4 Color;

in vec2 UVtrans;
out vec4 color;

void main()
{
    
        color = texture(SS, UVtrans); 
        
        //color = Color;
}

顶点着色器:

#version 300 es
layout(location = 0) in vec2 Vertex;
layout(location = 1) in vec2 UV;

uniform vec4 ColorIn;
uniform mat4 QuadMatrix;
out vec2 UVtrans;
out vec4 Color;

void main()
{
    gl_Position = QuadMatrix* vec4(Vertex, 0.0, 1.0);
    gl_Position.w = 1.0;
    UVtrans = UV;
    Color = ColorIn;
}

用于将纹理绑定(bind)到四边形的部分代码:

    public void Draw()
        {
            
            GL.UseProgram(VSID);
            Vector3 SS = new Vector3((new Vector(1, 1) * (Position - Offset)));
            SS.Z = Layer * 0.1f;
            Matrix4 Scale = Matrix4.CreateScale(Width, Height, 0);
            Matrix4 Translation = Matrix4.CreateTranslation(SS);
            
            Matrix4 ViewPoint = Matrix4.CreateOrthographic(Game.window.Width , Game.window.Height, -1,1000);
            Matrix4 Rotation = Matrix4.CreateRotationZ((float)Angle);

            Matrix4 Combined = Scale * Rotation * Translation * ViewPoint ;

            GL.ProgramUniformMatrix4(VSID, GL.GetUniformLocation(VSID, "QuadMatrix"), false, ref Combined);
            GL.ProgramUniform4(VSID, GL.GetUniformLocation(VSID, "ColorIn"), Color);
            GL.ProgramUniform1(VSID, GL.GetUniformLocation(VSID, "SS"), Texture);

            GL.ActiveTexture(TextureUnit.Texture0);
            GL.BindTexture(TextureTarget.Texture2D, 0);
            GL.BindVertexArray(QID);
            GL.DrawArrays(PrimitiveType.Triangles, 0, 6);
            GL.Enable(EnableCap.Texture2D);
            GL.Color3(Color);
            
        }

四边形形状生成器:

    public static void CreateQuad()
        {
            QID = GL.GenVertexArray();
            GL.BindVertexArray(QID);

            int VID =GL.GenBuffer();
            float[] Verticles = 
            {
                -0.5f,  0.5f,
                 0.5f,  0.5f,
                -0.5f, -0.5f,
                -0.5f, -0.5f,
                 0.5f,  0.5f,
                 0.5f, -0.5f


            };
            GL.BindBuffer(BufferTarget.ArrayBuffer, VID);
            GL.BufferData(BufferTarget.ArrayBuffer, sizeof(float)*Verticles.Length, Verticles,BufferUsageHint.StaticDraw);

            GL.VertexAttribPointer(0, 2, VertexAttribPointerType.Float, false, 0, 0);
            GL.EnableVertexAttribArray(0);
            
            int UVID = GL.GenBuffer();
            float[] UVs =
            {
                0, 1,
                1, 1,
                0, 0,
                0, 0,
                1, 1,
                1, 0
            };
            GL.BindBuffer(BufferTarget.ArrayBuffer, UVID);
            GL.BufferData(BufferTarget.ArrayBuffer, sizeof(float) * UVs.Length, UVs, BufferUsageHint.StaticDraw);

            GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, 0, 0);
            GL.EnableVertexAttribArray(1);
        }

纹理加载器:

    public static int LoadTexture(string path)
        {
            if (!File.Exists("Content/" + path))
            {
                throw new FileNotFoundException("file not found at Content/" + path);
            }

            int ID = GL.GenTexture();
            GL.BindTexture(TextureTarget.Texture2D, ID);

            Bitmap BMP = new Bitmap("Content/" + path);
            BitmapData data = BMP.LockBits(
                new Rectangle(0, 0, BMP.Width, BMP.Height),
                ImageLockMode.ReadOnly,System.Drawing.Imaging.PixelFormat.Format32bppArgb);

            //int ID = GL.GenTexture();
            //GL.BindTexture(TextureTarget.Texture2D, ID);

            GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, data.Width, data.Height,
                0, OpenTK.Graphics.OpenGL.PixelFormat.Bgra, PixelType.UnsignedByte, data.Scan0);

            BMP.UnlockBits(data);

            GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int)TextureWrapMode.Clamp);
            GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Clamp);

            GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Linear);
            GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);

            
            return ID;

        }

没有错误信息

Answer 1

必须设置为纹理采样器统一的值不是纹理对象(名称)值。它必须是纹理单元的索引。这意味着 TextureUnit.Texture0 为 0，TextureUnit.Texture1 为 1 ...

GL.ProgramUniform1(VSID, GL.GetUniformLocation(VSID, "SS"), Texture);

GL.ProgramUniform1(VSID, GL.GetUniformLocation(VSID, "SS"), 0);

但是在绘制对象之前，您必须将纹理对象绑定(bind)到设置为统一的纹理单元:

GL.ActiveTexture(TextureUnit.Texture0);
GL.BindTexture(TextureTarget.Texture2D, Texture);

GL.BindVertexArray(QID);
GL.DrawArrays(PrimitiveType.Triangles, 0, 6);

请注意，BindTexture将命名纹理对象绑定(bind)到指定目标的事件纹理单元。事件纹理单元由 ActiveTexture 设置.
纹理采样器uniform与纹理的绑定(bind)点是纹理单元的索引。

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分别在OpenGL ES 3.2中GLSL ES 3.2 , Binding point也可以在着色器代码中设置(类似于属性位置):

layout(binding = 0) uniform sampler2D SS;