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    • By Fadey Duh
      Good evening everyone!

      I was wondering if there is something equivalent of  GL_NV_blend_equation_advanced for AMD?
      Basically I'm trying to find more compatible version of it.

      Thank you!
    • By Jens Eckervogt
      Hello guys, 
      Please tell me! 
      How do I know? Why does wavefront not show for me?
      I already checked I have non errors yet.
      using OpenTK; using System.Collections.Generic; using System.IO; using System.Text; namespace Tutorial_08.net.sourceskyboxer { public class WaveFrontLoader { private static List<Vector3> inPositions; private static List<Vector2> inTexcoords; private static List<Vector3> inNormals; private static List<float> positions; private static List<float> texcoords; private static List<int> indices; public static RawModel LoadObjModel(string filename, Loader loader) { inPositions = new List<Vector3>(); inTexcoords = new List<Vector2>(); inNormals = new List<Vector3>(); positions = new List<float>(); texcoords = new List<float>(); indices = new List<int>(); int nextIdx = 0; using (var reader = new StreamReader(File.Open("Contents/" + filename + ".obj", FileMode.Open), Encoding.UTF8)) { string line = reader.ReadLine(); int i = reader.Read(); while (true) { string[] currentLine = line.Split(); if (currentLine[0] == "v") { Vector3 pos = new Vector3(float.Parse(currentLine[1]), float.Parse(currentLine[2]), float.Parse(currentLine[3])); inPositions.Add(pos); if (currentLine[1] == "t") { Vector2 tex = new Vector2(float.Parse(currentLine[1]), float.Parse(currentLine[2])); inTexcoords.Add(tex); } if (currentLine[1] == "n") { Vector3 nom = new Vector3(float.Parse(currentLine[1]), float.Parse(currentLine[2]), float.Parse(currentLine[3])); inNormals.Add(nom); } } if (currentLine[0] == "f") { Vector3 pos = inPositions[0]; positions.Add(pos.X); positions.Add(pos.Y); positions.Add(pos.Z); Vector2 tc = inTexcoords[0]; texcoords.Add(tc.X); texcoords.Add(tc.Y); indices.Add(nextIdx); ++nextIdx; } reader.Close(); return loader.loadToVAO(positions.ToArray(), texcoords.ToArray(), indices.ToArray()); } } } } } And It have tried other method but it can't show for me.  I am mad now. Because any OpenTK developers won't help me.
      Please help me how do I fix.

      And my download (mega.nz) should it is original but I tried no success...
      - Add blend source and png file here I have tried tried,.....  
      PS: Why is our community not active? I wait very longer. Stop to lie me!
      Thanks !
    • By codelyoko373
      I wasn't sure if this would be the right place for a topic like this so sorry if it isn't.
      I'm currently working on a project for Uni using FreeGLUT to make a simple solar system simulation. I've got to the point where I've implemented all the planets and have used a Scene Graph to link them all together. The issue I'm having with now though is basically the planets and moons orbit correctly at their own orbit speeds.
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    • By Jens Eckervogt
      Hello everyone, 
      I have problem with texture
      using System; using OpenTK; using OpenTK.Input; using OpenTK.Graphics; using OpenTK.Graphics.OpenGL4; using System.Drawing; using System.Reflection; namespace Tutorial_05 { class Game : GameWindow { private static int WIDTH = 1200; private static int HEIGHT = 720; private static KeyboardState keyState; private int vaoID; private int vboID; private int iboID; private Vector3[] vertices = { new Vector3(-0.5f, 0.5f, 0.0f), // V0 new Vector3(-0.5f, -0.5f, 0.0f), // V1 new Vector3(0.5f, -0.5f, 0.0f), // V2 new Vector3(0.5f, 0.5f, 0.0f) // V3 }; private Vector2[] texcoords = { new Vector2(0, 0), new Vector2(0, 1), new Vector2(1, 1), new Vector2(1, 0) }; private int[] indices = { 0, 1, 3, 3, 1, 2 }; private string vertsrc = @"#version 450 core in vec3 position; in vec2 textureCoords; out vec2 pass_textureCoords; void main(void) { gl_Position = vec4(position, 1.0); pass_textureCoords = textureCoords; }"; private string fragsrc = @"#version 450 core in vec2 pass_textureCoords; out vec4 out_color; uniform sampler2D textureSampler; void main(void) { out_color = texture(textureSampler, pass_textureCoords); }"; private int programID; private int vertexShaderID; private int fragmentShaderID; private int textureID; private Bitmap texsrc; public Game() : base(WIDTH, HEIGHT, GraphicsMode.Default, "Tutorial 05 - Texturing", GameWindowFlags.Default, DisplayDevice.Default, 4, 5, GraphicsContextFlags.Default) { } protected override void OnLoad(EventArgs e) { base.OnLoad(e); CursorVisible = true; GL.GenVertexArrays(1, out vaoID); GL.BindVertexArray(vaoID); GL.GenBuffers(1, out vboID); GL.BindBuffer(BufferTarget.ArrayBuffer, vboID); GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)(vertices.Length * Vector3.SizeInBytes), vertices, BufferUsageHint.StaticDraw); GL.GenBuffers(1, out iboID); GL.BindBuffer(BufferTarget.ElementArrayBuffer, iboID); GL.BufferData(BufferTarget.ElementArrayBuffer, (IntPtr)(indices.Length * sizeof(int)), indices, BufferUsageHint.StaticDraw); vertexShaderID = GL.CreateShader(ShaderType.VertexShader); GL.ShaderSource(vertexShaderID, vertsrc); GL.CompileShader(vertexShaderID); fragmentShaderID = GL.CreateShader(ShaderType.FragmentShader); GL.ShaderSource(fragmentShaderID, fragsrc); GL.CompileShader(fragmentShaderID); programID = GL.CreateProgram(); GL.AttachShader(programID, vertexShaderID); GL.AttachShader(programID, fragmentShaderID); GL.LinkProgram(programID); // Loading texture from embedded resource texsrc = new Bitmap(Assembly.GetEntryAssembly().GetManifestResourceStream("Tutorial_05.example.png")); textureID = GL.GenTexture(); GL.BindTexture(TextureTarget.Texture2D, textureID); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)All.Linear); GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)All.Linear); GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, texsrc.Width, texsrc.Height, 0, PixelFormat.Bgra, PixelType.UnsignedByte, IntPtr.Zero); System.Drawing.Imaging.BitmapData bitmap_data = texsrc.LockBits(new Rectangle(0, 0, texsrc.Width, texsrc.Height), System.Drawing.Imaging.ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppRgb); GL.TexSubImage2D(TextureTarget.Texture2D, 0, 0, 0, texsrc.Width, texsrc.Height, PixelFormat.Bgra, PixelType.UnsignedByte, bitmap_data.Scan0); texsrc.UnlockBits(bitmap_data); GL.Enable(EnableCap.Texture2D); GL.BufferData(BufferTarget.TextureBuffer, (IntPtr)(texcoords.Length * Vector2.SizeInBytes), texcoords, BufferUsageHint.StaticDraw); GL.BindAttribLocation(programID, 0, "position"); GL.BindAttribLocation(programID, 1, "textureCoords"); } protected override void OnResize(EventArgs e) { base.OnResize(e); GL.Viewport(0, 0, ClientRectangle.Width, ClientRectangle.Height); } protected override void OnUpdateFrame(FrameEventArgs e) { base.OnUpdateFrame(e); keyState = Keyboard.GetState(); if (keyState.IsKeyDown(Key.Escape)) { Exit(); } } protected override void OnRenderFrame(FrameEventArgs e) { base.OnRenderFrame(e); // Prepare for background GL.Clear(ClearBufferMask.ColorBufferBit); GL.ClearColor(Color4.Red); // Draw traingles GL.EnableVertexAttribArray(0); GL.EnableVertexAttribArray(1); GL.BindVertexArray(vaoID); GL.UseProgram(programID); GL.BindBuffer(BufferTarget.ArrayBuffer, vboID); GL.VertexAttribPointer(0, 3, VertexAttribPointerType.Float, false, 0, IntPtr.Zero); GL.ActiveTexture(TextureUnit.Texture0); GL.BindTexture(TextureTarget.Texture3D, textureID); GL.BindBuffer(BufferTarget.ElementArrayBuffer, iboID); GL.DrawElements(BeginMode.Triangles, indices.Length, DrawElementsType.UnsignedInt, 0); GL.DisableVertexAttribArray(0); GL.DisableVertexAttribArray(1); SwapBuffers(); } protected override void OnClosed(EventArgs e) { base.OnClosed(e); GL.DeleteVertexArray(vaoID); GL.DeleteBuffer(vboID); } } } I can not remember where do I add GL.Uniform2();
    • By Jens Eckervogt
      Hello everyone
      For @80bserver8 nice job - I have found Google search. How did you port from Javascript WebGL to C# OpenTK.?
      I have been searched Google but it shows f***ing Unity 3D. I really want know how do I understand I want start with OpenTK But I want know where is porting of Javascript and C#?
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OpenGL Textures withing texture?

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Hello people! :) Im making a tile-based game. Each tile is an image loaded by sdl and converted to opengl texture. The redrawing part of the loop looks like this: glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glLoadIdentity(); glBindTexture(GL_TEXTURE_2D, textureid); for(int x=0;x<22;x++){ for(int y=0;y<17;y++) { glBegin(GL_QUADS); // bottom left glTexCoord2f(0, 0); glVertex2f(32*x+xpos, 32*y+ypos); // bottom right glTexCoord2f(1, 0); glVertex2f(32*x+32+xpos, 32*y+ypos); // top right glTexCoord2f(1, 1); glVertex2f(32*x+32+xpos, 32*y+32+ypos); // top left glTexCoord2f(0, 1); glVertex2f(32*x+xpos, 32*y+32+ypos); glEnd(); } } The code is pretty straight forward so I didnt comment a lot. As you can see, the texture is redrawn 22*17 times. Is there a way to combine those 22*17 textures into one for performance benefits? Thank you.

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I'm assuming you meant that you have many textures and you put
glBindTexture(GL_TEXTURE_2D, textureid);
in your for loop.

Yes, you can make 1 larger texture by putting all the smaller ones together and adjust the texture coordinates accordingly.
Of course, if you are using mipmapping, care must be taken so that the mipmaps are properly generated.

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Currently, you render ONE texture 17 x 22 times. Is this what you actually wanted?

Your problem is essentially a geometry and texture issue. The geometry can be better optimized by creating the grid once by(a) a display list, or (b) using a 3D modeling tool and importing the resulting grid back into your application. (c) Transforming the data into a vertex array format.

Since by the description of you problem the code/application is small scale - I would recommend the display list approach.

The code below is an example of creating a new display list. For this approach to work you still require your tile-grid drawing routine. Perhaps calling it drawTileGrid()

uint aDisplayListID = glGenLists (1);
glNewList (glDisplayListID, Gl.GL_COMPILE);
... place a call to your standard grid drawing code here
glEndList ();

Then in your render loop you simply perform this call instead:

glCallList (aDisplayListID);

What has this done? The original drawTileGrid() code was now been captured and stored within the Video cards memory. Thus making subsequent calls to draw it much much faster.

If you need to switch between different textures this is okay too. Simply perform the glBindTexture() command in the inner body of your loop.
Of course you need some way of controlling WHICH texture is appropriate but that's your application specific code bit.

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Yes you can have "textures within textures" :) You simply change the texture coordinates to the section of the texture you want to use.

Ignoring my crappy coder art, this image shows a 512x512 texture with four "sub textures in it": Here

As you can see to access each "sub texture" you just change the tex coords. This means you can have the same texture bound for many different tiles if you wanted to. I use one texture for my world tiles and another for my unit tiles, so I can draw the whole world and all its units with just two texture binds.

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Thank you very much ZeroSum, BionicBytes and V-man. All of your answers were very helpfull. I optimized the drawing routine by calling the list code and saved all my tile graphics in one bmp file.

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Im having a problem with the display list. When a new tile is reached while walking, I want the display list to clear and redraw different tiles in it(x-1 when moved left etc). Here is what I have so far:

void reLoadTiles(){
glBindTexture(GL_TEXTURE_2D, textureYou); // textureYou is the bmp file that stores all kinds of 32x32 pix tiles

glNewList (DisplayListID, GL_COMPILE);

for(int x=0;x<22;x++){
for(int y=0;y<17;y++) {
posX = tileMap[currentTileX+x][currentTileY+y].tilePosX;
//the tilePosX stores the fraction that represents the tile that should be drawn (for example when there are 5x5 tiles in a bmp file, tilePosX would be position of the tile + 1/5...)

posY = tileMap[currentTileX+x][currentTileY+y].tilePosY;

// bottom left
glVertex2f(32*x, 32*y);
// bottom right
glVertex2f(32*x+32, 32*y);
// top right
glTexCoord2f(posX+(float)1/mapWidth, posY+(float)1/mapHeight);
glVertex2f(32*x+32, 32*y+32);
// top left
glTexCoord2f(posX, posY+(float)1/mapHeight);
glVertex2f(32*x, 32*y+32);
glEndList ();


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So what you have is an atlas based texture. I.e a texture that has NxM textures on it. Presumably matching this is a piece of geometry arranged as a grid. The texture coordinates are arranged in such as way as to mimic the NxM tile based textures. Is this correct?

What's not so clear is the 'when a new tile is reached'. Sounds like your wanting to dynamically generate a new set of extra tiles.
Perhaps there is an alternative method - why not simply reuse the exiting grid. You could simply displace the grid 'n' units along the XZ axis using a translate () command before you issue the glCallList () command. To update the tile - if you have access to the original data then use this to update a chunk of the texture atlas using glTexCopy2D().

This approach might be better than regenerating the entire geometry grid every time you want to give the illusion of moving/shifting a tile to the left/right etc...

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