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OpenGL / SharpGL:渲染2D图像水平拉伸

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我正在玩C#中的OpenGL(使用SharpGL),我来自DirectX背景......我认为OpenGL非常相似,而且它有点像,除了我的投影矩阵有问题导致我的2D图像水平拉伸一点(让Lena看起来非常臃肿) .

我认为我的问题源于我的正投影,但我并不积极 - 我在绘图函数中填充了一个投影,以确保它按预期工作 . 纹理正确地渲染到顶点,图像为512:512作为BMP(在拉入C#时验证) .

也许有人可以看看我的代码并帮助我?我从其他示例中复制了大部分代码,并且稍微摆弄了它,所以这是我最新的化身:

private bool TexturesInitialised = false;
    private Bitmap gImage1;
    private System.Drawing.Imaging.BitmapData gbitmapdata;
    private uint[] gtexture = new uint[1];

    private void InitialiseTexture(ref OpenGL gl)
    {
        gImage1 = new Bitmap(@"C:\Users\SJ\Pictures\lenaV.bmp");

        Rectangle rect = new Rectangle(0, 0, gImage1.Width, gImage1.Height);
        gbitmapdata = gImage1.LockBits(rect, System.Drawing.Imaging.ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
        gImage1.UnlockBits(gbitmapdata);
        gl.GenTextures(1, gtexture);
        gl.BindTexture(OpenGL.GL_TEXTURE_2D, gtexture[0]);
        gl.TexImage2D(OpenGL.GL_TEXTURE_2D, 0, (int)OpenGL.GL_RGBA, gImage1.Width, gImage1.Height, 0, OpenGL.GL_BGR_EXT, OpenGL.GL_UNSIGNED_BYTE, gbitmapdata.Scan0);

        gl.TexParameter(OpenGL.GL_TEXTURE_2D, OpenGL.GL_TEXTURE_MIN_FILTER, OpenGL.GL_LINEAR);
        gl.TexParameter(OpenGL.GL_TEXTURE_2D, OpenGL.GL_TEXTURE_MAG_FILTER, OpenGL.GL_LINEAR);

        TexturesInitialised = true;
    }

    private void openGLControl_OpenGLDraw(object sender, RenderEventArgs e)
    {
        //  Get the OpenGL object.
        OpenGL gl = openGLControl.OpenGL;

        //  Clear the color and depth buffer.
        gl.Clear(OpenGL.GL_COLOR_BUFFER_BIT | OpenGL.GL_DEPTH_BUFFER_BIT);

        //  Load the identity matrix.
        gl.LoadIdentity();

        if (!TexturesInitialised)
        {
            InitialiseTexture(ref gl);
        }

        gl.Enable(OpenGL.GL_TEXTURE_2D);
        gl.BindTexture(OpenGL.GL_TEXTURE_2D, gtexture[0]);
        gl.Color(1.0f, 1.0f, 1.0f, 0.1f);
        gl.Begin(OpenGL.GL_QUADS);

        gl.TexCoord(1.0f, 1.0f);
        gl.Vertex(gImage1.Width, gImage1.Height, 1.0f);

        gl.TexCoord(0.0f, 1.0f);
        gl.Vertex(0.0f, gImage1.Height, 1.0f);

        gl.TexCoord(0.0f, 0.0f);
        gl.Vertex(0.0f, 0.0f, 1.0f);

        gl.TexCoord(1.0f, 0.0f);
        gl.Vertex(gImage1.Width, 0.0f, 1.0f);

        gl.End();
        gl.Disable(OpenGL.GL_TEXTURE_2D);

        gl.MatrixMode(OpenGL.GL_PROJECTION);
        gl.LoadIdentity();
        gl.Ortho(0.0, (double)gImage1.Width, (double)gImage1.Height, 0.0, -1.0, 1.0);
        gl.MatrixMode(OpenGL.GL_MODELVIEW);
        gl.Disable(OpenGL.GL_DEPTH_TEST);
    }

    private void openGLControl_OpenGLInitialized(object sender, EventArgs e)
    {
        //  Get the OpenGL object.
        OpenGL gl = openGLControl.OpenGL;

        //  Set the clear color.
        gl.ClearColor(0, 0, 0, 0);
    }

    private void openGLControl_Resized(object sender, EventArgs e)
    {
        OpenGL gl = openGLControl.OpenGL;
        gl.MatrixMode(OpenGL.GL_PROJECTION);
        gl.LoadIdentity();
        if (!TexturesInitialised)
        {
            gl.Ortho(-1, 1, -1, 1, -1, 1);
        }
        else
        {
            gl.Ortho(0, gImage1.Width, gImage1.Height, 0, -1, 1);
        }
        gl.MatrixMode(OpenGL.GL_MODELVIEW);
        gl.Disable(OpenGL.GL_DEPTH_TEST);
    }

1 回答

  • 1

    完全归功于GeirGrusom . 改变就像设置一样简单:

    gl.Ortho(0.0, (double)gImage1.Width, (double)gImage1.Height, 0.0, -1.0, 1.0);
    

    至:

    gl.Ortho(0.0, (double)openGLControl.Width, (double)openGLControl.Height, 0.0, -1.0, 1.0);
    

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