OpenGL C# (OpenTK) 加载和绘制图像功能不起作用 [英] OpenGL C# (OpenTK) Load and Draw Image functions not working

问题描述

我正在尝试在屏幕上加载和显示纹理，但是我收到了一个黑框，用于显示它.

I'm trying to load and display a texture on the screen, however am receiving a black box where it is meant to be shown.

两个主要方法是LoadTexture"和Draw Image"，我假设错误在其中之一.

The two main methods are "LoadTexture" and "Draw Image", I'm assuming the mistake is in one of them.

using System;
using System.Diagnostics;
using OpenTK;
using OpenTK.Graphics;
using OpenTK.Graphics.OpenGL;
using System.Drawing;
using System.Drawing.Imaging;

namespace FailRender
{
    public class FailRender: GameWindow
    {
        public FailRender() : base(800, 600, GraphicsMode.Default, "Hoard of Upgrades")
        {
            GL.ClearColor(0, 0.1f, 0.4f, 1);

            texture = LoadTexture("sand.jpg");
        }

        private int texture;

        public int LoadTexture(string file)
        {
            Bitmap bitmap = new Bitmap(file);

            int tex;
            GL.Hint(HintTarget.PerspectiveCorrectionHint, HintMode.Nicest);

            GL.GenTextures(1, out tex);
            GL.BindTexture(TextureTarget.Texture2D, tex);

            BitmapData data = bitmap.LockBits(new System.Drawing.Rectangle(0, 0, bitmap.Width, bitmap.Height),
                ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppRgb);

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

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

            return tex;
        }

        public static void DrawImage(int image)
        {
            GL.MatrixMode(MatrixMode.Projection);
            GL.PushMatrix();
            GL.LoadIdentity();

            GL.Ortho(0, 800, 0, 600, -1, 1);

            GL.MatrixMode(MatrixMode.Modelview);
            GL.PushMatrix();
            GL.LoadIdentity();

            GL.Disable(EnableCap.Lighting);

            GL.Enable(EnableCap.Texture2D);

            GL.Color4(1, 0, 0, 1);

            GL.BindTexture(TextureTarget.Texture2D, image);

            GL.Begin(BeginMode.Quads);

            GL.TexCoord2(0, 0);
            GL.Vertex3(0, 0, 0);

            GL.TexCoord2(1, 0);
            GL.Vertex3(256, 0, 0);

            GL.TexCoord2(1, 1);
            GL.Vertex3(256, 256, 0);

            GL.TexCoord2(0, 1);
            GL.Vertex3(0, 256, 0);

            GL.End();

            GL.Disable(EnableCap.Texture2D);
            GL.PopMatrix();

            GL.MatrixMode(MatrixMode.Projection);
            GL.PopMatrix();

            GL.MatrixMode(MatrixMode.Modelview);
        } 

        protected override void OnRenderFrame( FrameEventArgs e )
        {
            GL.Clear( ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit );

            DrawImage(texture);

            SwapBuffers();
        }
    }

    public class Program
    {
        [STAThread]
        public static void Main()
        {
            using (FailRender win = new FailRender())
            {
                win.Run();
            }
        }
    }
}

推荐答案

删除行GL.Color4(1, 0, 0, 1);"

Removing the line "GL.Color4(1, 0, 0, 1);"

并将加载纹理功能更改为:

and changing the load texture function to:

public int LoadTexture(string file)
{
    Bitmap bitmap = new Bitmap(file);

    int tex;
    GL.Hint(HintTarget.PerspectiveCorrectionHint, HintMode.Nicest);

    GL.GenTextures(1, out tex);
    GL.BindTexture(TextureTarget.Texture2D, tex);

    BitmapData data = bitmap.LockBits(new System.Drawing.Rectangle(0, 0, bitmap.Width, bitmap.Height),
        ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);

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


    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int) TextureMinFilter.Linear);
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int) TextureMagFilter.Linear);
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapS, (int) TextureWrapMode.Repeat);
    GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int) TextureWrapMode.Repeat);

    return tex;
}

解决了这个问题.System.Drawing.PixelFormat.Argb 使用 OpenGL 格式 Bgra.

Fixes the issue. System.Drawing.PixelFormat.Argb goes with OpenGL format Bgra.

这篇关于OpenGL C# (OpenTK) 加载和绘制图像功能不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！