CoordinateSystems.cs

using OpenGL_Testbed.Lib;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Graphics.OpenGL;
using System;
using System.IO;

namespace OpenGL_Testbed
{
    public class CoordinateSystems : GameWindow
    {
        private ShaderProgram shaderProgram;
        private VertexBuffer vbo;
        private VertexArray vao;
        private Texture texture1;
        private Texture texture2;
        private Matrix4 view;
        private Matrix4 projection;

        private readonly float[] vertices =
        {
            -0.5f, -0.5f, -0.5f,  0.0f, 0.0f,
            0.5f, -0.5f, -0.5f,  1.0f, 0.0f,
            0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
            0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
            -0.5f,  0.5f, -0.5f,  0.0f, 1.0f,
            -0.5f, -0.5f, -0.5f,  0.0f, 0.0f,

            -0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
            0.5f, -0.5f,  0.5f,  1.0f, 0.0f,
            0.5f,  0.5f,  0.5f,  1.0f, 1.0f,
            0.5f,  0.5f,  0.5f,  1.0f, 1.0f,
            -0.5f,  0.5f,  0.5f,  0.0f, 1.0f,
            -0.5f, -0.5f,  0.5f,  0.0f, 0.0f,

            -0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
            -0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
            -0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
            -0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
            -0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
            -0.5f,  0.5f,  0.5f,  1.0f, 0.0f,

            0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
            0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
            0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
            0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
            0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
            0.5f,  0.5f,  0.5f,  1.0f, 0.0f,

            -0.5f, -0.5f, -0.5f,  0.0f, 1.0f,
            0.5f, -0.5f, -0.5f,  1.0f, 1.0f,
            0.5f, -0.5f,  0.5f,  1.0f, 0.0f,
            0.5f, -0.5f,  0.5f,  1.0f, 0.0f,
            -0.5f, -0.5f,  0.5f,  0.0f, 0.0f,
            -0.5f, -0.5f, -0.5f,  0.0f, 1.0f,

            -0.5f,  0.5f, -0.5f,  0.0f, 1.0f,
            0.5f,  0.5f, -0.5f,  1.0f, 1.0f,
            0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
            0.5f,  0.5f,  0.5f,  1.0f, 0.0f,
            -0.5f,  0.5f,  0.5f,  0.0f, 0.0f,
            -0.5f,  0.5f, -0.5f,  0.0f, 1.0f
        };

        public CoordinateSystems() : base(800, 600, GraphicsMode.Default, "Test Game", GameWindowFlags.FixedWindow, DisplayDevice.Default, 3, 3, GraphicsContextFlags.Default) { }

        protected override void OnResize(EventArgs e)
        {
            base.OnResize(e);
            GL.Viewport(0, 0, this.Width, this.Height);
        }

        protected override void OnLoad(EventArgs e)
        {
            //Setup the viewport
            GL.Viewport(0, 0, this.Width, this.Height);

            //Load the texture
            try
            {
                texture1 = new Texture("resources/textures/container.jpg");
                texture2 = new Texture("resources/textures/awesomeface.png");
            }
            catch (FileNotFoundException fnf)
            {
                Console.Write(fnf.ToString());
            }

            //Create a vertex shader
            Shader vertShader = Shader.CreateShaderFromFile(ShaderType.VertexShader, "coordSystemsVertex");

            //Create a fragment shader
            Shader fragShader = Shader.CreateShaderFromFile(ShaderType.FragmentShader, "coordSystemsFragment");

            //Create a shader program
            shaderProgram = new ShaderProgram();
            shaderProgram.Attach(vertShader, true);
            shaderProgram.Attach(fragShader, true);
            shaderProgram.Link("shaderProgram");

            vao = new VertexArray();

            vao.Bind();
            //Create a VBO(Vertex Buffer Object)
            vbo = new VertexBuffer();
            vbo.Bind();
            vbo.SetData(vertices, BufferUsageHint.StaticDraw);

            GL.VertexAttribPointer(0, 3, VertexAttribPointerType.Float, false, 5 * sizeof(float), 0);
            GL.EnableVertexAttribArray(0);

            GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, 5 * sizeof(float), 3 * sizeof(float));
            GL.EnableVertexAttribArray(1);

            vbo.Unbind();
            vao.Unbind();

            shaderProgram.Use();
            shaderProgram.SetUniform("texture1", 0);
            shaderProgram.SetUniform("texture2", 1);

            view = Matrix4.CreateTranslation(0.0F, 0.0F, -3.0F);
            projection = Matrix4.CreatePerspectiveFieldOfView(MathHelper.DegreesToRadians(45.0F), (float)Width / Height, 0.1F, 100.0F);
            shaderProgram.SetUniform("view", view);
            shaderProgram.SetUniform("projection", projection);
        }

        protected override void OnRenderFrame(FrameEventArgs e)
        {
            base.OnRenderFrame(e);
            GL.Enable(EnableCap.DepthTest);
            GL.ClearColor(0.2f, 0.3f, 0.3f, 1.0f);
            GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);

            GL.ActiveTexture(TextureUnit.Texture0);
            texture1.Bind();
            GL.ActiveTexture(TextureUnit.Texture1);
            texture2.Bind();

            Vector3[] cubePositions = 
            {
                new Vector3( 0.0f,  0.0f,  0.0f),
                new Vector3( 2.0f,  5.0f, -15.0f),
                new Vector3(-1.5f, -2.2f, -2.5f),
                new Vector3(-3.8f, -2.0f, -12.3f),
                new Vector3( 2.4f, -0.4f, -3.5f),
                new Vector3(-1.7f,  3.0f, -7.5f),
                new Vector3( 1.3f, -2.0f, -2.5f),
                new Vector3( 1.5f,  2.0f, -2.5f),
                new Vector3( 1.5f,  0.2f, -1.5f),
                new Vector3(-1.3f,  1.0f, -1.5f)
            };

            vao.Bind();
            for(int i = 0; i < 10; i++)
            {
                Matrix4 model = Matrix4.CreateFromAxisAngle(new Vector3(1.0f, 0.3f, 0.5f), MathHelper.DegreesToRadians(20.0F / 100 * Environment.TickCount)) * Matrix4.CreateTranslation(cubePositions[i]);
                shaderProgram.SetUniform("model", model);

                GL.DrawArrays(PrimitiveType.Triangles, 0, 36);
            }
            vao.Unbind();

            SwapBuffers();
        }

        protected override void OnClosed(EventArgs e)
        {
            base.OnClosed(e);

            //Cleanup
            vao.Delete();
            vbo.Delete();
        }
    }
}