使用OpenGL和GLKViewController以及Xamarin繪制三角形

Question

我想畫一個三角形打招呼（或四）與GLViewController就像在這個 Xamarin例如對OpenGL

該示例創建了自己的FrameBuffers和其他邏輯，據我了解，GLView已通過閱讀此處的Apple文檔完成了此操作

我正在使用從主Storyboard中的GLKViewController派生的類

班級應使用黑色到紅色的動畫效果清除背景（實際上是有效的），並在屏幕上繪制四邊形（無效）

這是我到目前為止得到的代碼：

partial class GpuImageView : MonoTouch.GLKit.GLKViewController
{
    public GpuImageView (IntPtr handle) : base (handle)
    {

    }

    GLKView glkView;
    EAGLContext Context;

    public override void ViewDidLoad()
    {
        base.ViewDidLoad();

        //create the rendering context
        Context = new EAGLContext(EAGLRenderingAPI.OpenGLES2);

        //get the view:
        glkView = (GLKView)this.View;

        glkView.Context = Context;
        glkView.MultipleTouchEnabled = true;

        glkView.DrawInRect  += Draw;

    }

    public override void Update()
    {
        color = ( color > 1.0F ) ? (0F ) : (color +   1.0F / 30.0F);
    }

    float color ;
    void Draw (object sender, GLKViewDrawEventArgs e)
    {
        GL.Viewport(0, 0, glkView.DrawableWidth, glkView.DrawableHeight);

        //this matrix initialization is copied from the OpenGLES example:
        GL.MatrixMode (All.Projection);
        GL.LoadIdentity ();
        GL.Ortho (-1.0f, 1.0f, -1.5f, 1.5f, -1.0f, 1.0f);
        GL.MatrixMode(All.Modelview);
        GL.LoadIdentity();

        float[] squareVertices = {
            -0.5f, -0.5f,
            0.5f, -0.5f,
            -0.5f, 0.5f, 
            0.5f, 0.5f,
        };
        byte[] squareColors = {
            255, 255,   0, 255,
            0,   255, 255, 255,
            0,     0,    0,  0,
            255,   0,  255, 255,
        };


        //The color clear is working fine :)
        GL.ClearColor(color, 0F, 0F, 1F);
        GL.Clear( ClearBufferMask.ColorBufferBit |  ClearBufferMask.DepthBufferBit);

        //The quad never draws:
        GL.VertexPointer (2, All.Float, 0, squareVertices);
        GL.EnableClientState (All.VertexArray);
        GL.ColorPointer (4, All.UnsignedByte, 0, squareColors);
        GL.EnableClientState (All.ColorArray);

        GL.DrawArrays (All.TriangleStrip, 0, 4);
    }

這是我正在使用的庫（在項目中添加了“ OpenTK-1.0”）：

using System;
using MonoTouch.Foundation;
using MonoTouch.UIKit;
using System.CodeDom.Compiler;
using MonoTouch.OpenGLES;
using MonoTouch.GLKit;
using OpenTK.Graphics.ES11;
using MonoTouch.CoreAnimation;

Answer 1

我正在使用OpenGLES2初始化EAGL上下文，更改為OpenGLES1解決了該問題