Beginner troubles with 2D projection and textures in OpenGL - c#

Lately I have been trying to learn/use OpenGL 3+. I have looked through tutorials and examples but I've run into a wall trying to get textures and 2D projection to work without problems.
The goal for now is to have a function which can draw a textured quad to the screen with it's position specified by pixels (not [-1,1]).
For readability and testing I made a new barebones program with the knowledge I currently have, and it exhibits nearly the same problems. Help would be appreciated since i'm starting to go bald over this :(..
The current code shows a garbled texture instead of the image itself (texture is 128x128px).
[Program.cs]
namespace OpenGLTester
{
static class Program
{
public static GameWindow window;
public static String programDirectory = Directory.GetCurrentDirectory();
public static int testTexture;
public static int uniform_fragment_texture;
public static int shaderProgram;
[STAThread]
static void Main()
{
window = new GameWindow(1024, 768, new GraphicsMode(new ColorFormat(8, 8, 8, 8), 0, 8), "OpenGLTester", GameWindowFlags.Default, DisplayDevice.Default, 3, 1, GraphicsContextFlags.Default);
GL.Viewport(new Size(1024,768));
shaderProgram = GL.CreateProgram();
int vertexShader = GL.CreateShader(ShaderType.VertexShader);
int fragmentShader = GL.CreateShader(ShaderType.FragmentShader);
GL.ShaderSource(vertexShader, File.ReadAllText(programDirectory + #"\vertex.vert"));
GL.ShaderSource(fragmentShader, File.ReadAllText(programDirectory + #"\fragment.frag"));
GL.CompileShader(vertexShader);
GL.CompileShader(fragmentShader);
GL.AttachShader(shaderProgram, vertexShader);
GL.AttachShader(shaderProgram, fragmentShader);
GL.LinkProgram(shaderProgram);
if (GL.GetError() != ErrorCode.NoError) { System.Diagnostics.Debugger.Break(); }
Console.WriteLine(GL.GetProgramInfoLog(shaderProgram));
GL.UseProgram(shaderProgram);
Matrix4 projectionMatrix = Matrix4.CreateOrthographic(1024, 768, 0, 1);
GL.UniformMatrix4(GL.GetUniformLocation(shaderProgram, "vertex_projection"), false, ref projectionMatrix);
uniform_fragment_texture = GL.GetUniformLocation(shaderProgram, "fragment_texture");
testTexture = loadTexture(programDirectory + #"\test.png");
GL.Disable(EnableCap.DepthTest);
GL.Disable(EnableCap.Lighting);
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactorSrc.One, BlendingFactorDest.OneMinusSrcAlpha);
window.UpdateFrame += window_UpdateFrame;
window.RenderFrame += window_RenderFrame;
window.Resize += window_Resize;
window.TargetRenderFrequency = 60;
window.Run();
}
static void window_Resize(object sender, EventArgs e)
{
//Don't allow resizing for now.
window.Size = new Size(1024, 768);
}
static void window_UpdateFrame(object sender, FrameEventArgs e)
{
ErrorCode currentError = GL.GetError();
if (currentError != ErrorCode.NoError)
{
Console.WriteLine(Enum.GetName(typeof(ErrorCode), currentError));
System.Diagnostics.Debugger.Break();
}
}
static void window_RenderFrame(object sender, FrameEventArgs e)
{
GL.ClearColor(0, 0, 0, 0);
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.StencilBufferBit);
//test texture is 128x128pixels.
drawTexRect(100, 228, 100, 228, testTexture);
window.SwapBuffers();
}
static int loadTexture(String filePath)
{
GL.Enable(EnableCap.Texture2D);
int id = GL.GenTexture();
GL.ActiveTexture(TextureUnit.Texture0);
GL.BindTexture(TextureTarget.Texture2D, id);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureBaseLevel, 0);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMaxLevel, 0);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Linear);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
Bitmap bmp = new Bitmap(filePath);
BitmapData bmp_data = bmp.LockBits(new Rectangle(0, 0, bmp.Width, bmp.Height), ImageLockMode.ReadOnly, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, bmp_data.Width, bmp_data.Height, 0,
OpenTK.Graphics.OpenGL.PixelFormat.Rgba, PixelType.UnsignedByte, bmp_data.Scan0);
bmp.UnlockBits(bmp_data);
bmp.Dispose();
return id;
}
static void drawTexRect(float top, float bottom, float left, float right, int texture)
{
//topLeft,bottomLeft,bottomRight,topRight
float[] vertices = new float[] {
left, top, 0, 0,
left, bottom, 0, 1,
right, bottom, 1, 1,
right, top, 1, 0,
};
int buffer = GL.GenBuffer();
GL.BindBuffer(BufferTarget.ArrayBuffer, buffer);
GL.BufferData<float>(BufferTarget.ArrayBuffer, new IntPtr(vertices.Length * sizeof(float)), vertices, BufferUsageHint.StaticDraw);
//vec2 - screen position
GL.EnableVertexAttribArray(0);
GL.VertexAttribPointer(0, 2, VertexAttribPointerType.Float, false, 4, 0);
//vec2 - texture coordinates
GL.EnableVertexAttribArray(1);
GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, 4, 2 * sizeof(float));
GL.Enable(EnableCap.Texture2D);
GL.ActiveTexture(TextureUnit.Texture0);
GL.BindTexture(TextureTarget.Texture2D, texture);
GL.Uniform1(uniform_fragment_texture, 0);
GL.DrawArrays(PrimitiveType.Quads, 0, 4);
GL.DeleteBuffer(buffer);
}
}
}
[vertex.vert]
#version 330
in vec2 vertex_position;
in vec2 vertex_texturePosition;
uniform mat4 vertex_projection;
out vec2 fragment_texturePosition;
void main()
{
gl_Position = vec4(vertex_position,0.0,1.0) * vertex_projection;
fragment_texturePosition = vertex_texturePosition;
}
[fragment.frag]
#version 330
in vec2 fragment_texturePosition;
uniform sampler2D fragment_texture;
out vec4 output_color;
void main()
{
output_color = texture(fragment_texture,fragment_texturePosition);
}
After changes suggested by #j-p one problem remains:
After texture position change suggested by #j-p:
The projection is also wrong given the position i expect it to be 100 px from the left and 100 px from the top, don't see how i can fix this..

The stride parameter is in byte:
GL.EnableVertexAttribArray(0);
GL.VertexAttribPointer(0, 2, VertexAttribPointerType.Float, false, 4 * sizeof(float), 0);
//vec2 - texture coordinates
GL.EnableVertexAttribArray(1);
GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, 4 * sizeof(float), 2 * sizeof(float));
Also,the corresponding opengl pixel format for windows argb bitmap is BGRA. (link)
GL.TexImage2D(TextureTarget.Texture2D, 0, PixelInternalFormat.Rgba, data.Width, data.Height, 0,**OpenTK.Graphics.OpenGL.PixelFormat.Bgra**, PixelType.UnsignedByte, data.Scan0);
And finally, your texture coordinates should be adjusted as follow:
float[] vertices = new float[] {
left, top, 0, 1,
left, bottom, 0, 0,
right, bottom, 1, 0,
right, top, 1, 1
};

Related

OpenTk OpenGl texture coordinate pointer not working

I pass the vertices to a buffer and the texture coordinates to an another buffer the vertices are draw perfectly, but the texture coordinate pointer is not doing anything, but in an another project it works without problems, I tried to copy from the other project but nothing happened. It produces the same problem without throwing any errors. However, it works perfectly in the immediate drawing mode.
void renderFrame(object o, FrameEventArgs e)
{
// Clear screen
GL.Translate(Input.GetMoveDir(.1f));
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureWrapT, (int)TextureWrapMode.Repeat);
//Render image
//Enable thing before use
GL.BindTexture(TextureTarget.Texture2D, texture.ID);
GL.Enable(EnableCap.Texture2D);
//Setup blending
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactor.SrcAlpha, BlendingFactor.OneMinusSrcAlpha);
// Immedaiate test
/*GL.Begin(BeginMode.Triangles);
for (int i = 0; i < vertexBuffer.Length; i++)
{
GL.Normal3(normalBuffer[i]);
GL.TexCoord2(uvBuffer[i]);
GL.Vertex3(vertexBuffer[i]);
}
GL.End();*/
//Enable arrays
GL.EnableClientState(ArrayCap.VertexArray);
GL.EnableClientState(ArrayCap.TextureCoordArray);
//GL.EnableClientState(ArrayCap.NormalArray);
//GL.Color3(Color.Red);
//Set vertex pointer
GL.BindBuffer(BufferTarget.ArrayBuffer, VEB);
GL.VertexPointer(3, VertexPointerType.Float, Vector3.SizeInBytes, 0);
//Set uv pointer
GL.BindBuffer(BufferTarget.ArrayBuffer, UVB);
GL.TexCoordPointer(2, TexCoordPointerType.Float, Vector2.SizeInBytes, 0);
//Set normal pointer
/*GL.BindBuffer(BufferTarget.ArrayBuffer, NOB);
GL.NormalPointer(NormalPointerType.Float, Vector3.SizeInBytes, 0);*/
//Draw
GL.DrawArrays(PrimitiveType.Quads, 0, vertexBuffer.Length);
// Swap buffers
GL.Flush();
window.SwapBuffers();
}
public void UpdateBuffers(Vector3[] vertices, Vector2[] uvs, Vector3[] normals)
{
//Vertex buffer
vertexBuffer = vertices;
GL.BindBuffer(BufferTarget.ArrayBuffer, VEB);
GL.BufferSubData<Vector3>(BufferTarget.ArrayBuffer, (IntPtr)0, (int)(Vector3.SizeInBytes * vertexBuffer.Length), vertexBuffer);
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
//Uv buffer
uvBuffer = uvs;
GL.BindBuffer(BufferTarget.ArrayBuffer, UVB);
GL.BufferSubData<Vector2>(BufferTarget.ArrayBuffer, (IntPtr)0, (int)(Vector2.SizeInBytes * uvBuffer.Length), uvBuffer);
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
//Normal buffer
normalBuffer = normals;
GL.BindBuffer(BufferTarget.ArrayBuffer, NOB);
GL.BufferSubData<Vector3>(BufferTarget.ArrayBuffer, (IntPtr)0, (int)(Vector3.SizeInBytes * normalBuffer.Length), normalBuffer);
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
Console.WriteLine("Buffers updated");
}

Rendering triangles with OpenTK from VBO

I cannot render triangles for the life of me with a VBO in OpenTK. I am loading my data to the VBO in glControl_Load() event. I get a background screen with no triangles when running. The data is a from a mesh m.OpenGLArrays(out data, out indices) outputs a list of floats and ints. The list of floats for the vertices T1v1, T1v2, T1v3, T2v1, T2v2, T2v3, .... , all three vertices for each triangle back to back.
However given a blank screen with the code when I comment the "intermediate" rendering code everything renders fine....??? What am I doing wrong?
private void glControl_Load(object sender, EventArgs e)
{
loaded = true;
glControl.MouseMove += new MouseEventHandler(glControl_MouseMove);
glControl.MouseWheel += new MouseEventHandler(glControl_MouseWheel);
GL.ClearColor(Color.DarkSlateGray);
GL.Color3(1f, 1f, 1f);
m.OpenGLArrays(out data, out indices);
this.indicesSize = (uint)indices.Length;
GL.GenBuffers(1, out VBOid[0]);
GL.GenBuffers(1, out VBOid[1]);
SetupViewport();
}
private void SetupViewport()
{
if (this.WindowState == FormWindowState.Minimized) return;
glControl.Width = this.Width - 32;
glControl.Height = this.Height - 80;
Frame_label.Location = new System.Drawing.Point(glControl.Width / 2, glControl.Height + 25);
GL.MatrixMode(MatrixMode.Projection);
//GL.LoadIdentity();
GL.Ortho(0, glControl.Width, 0, glControl.Height, -1, 1); // Bottom-left corner pixel has coordinate (0, 0)
GL.Viewport(0, 0, glControl.Width, glControl.Height); // Use all of the glControl painting area
GL.Enable(EnableCap.DepthTest);
GL.BindBuffer(BufferTarget.ArrayBuffer, VBOid[0]);
GL.BufferData(BufferTarget.ArrayBuffer, (IntPtr)(data.Length * sizeof(float)), data, BufferUsageHint.StaticDraw);
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
float aspect_ratio = this.Width / (float)this.Height;
projection = Matrix4.CreatePerspectiveFieldOfView(MathHelper.PiOver4, aspect_ratio, 1, 1024);
GL.MatrixMode(MatrixMode.Projection);
GL.LoadMatrix(ref projection);
}
private void glControl_Paint(object sender, PaintEventArgs e)
{
if (loaded)
{
GL.Clear(ClearBufferMask.ColorBufferBit |
ClearBufferMask.DepthBufferBit |
ClearBufferMask.StencilBufferBit);
modelview = Matrix4.LookAt(0f, 0f, -200f + zoomFactor, 0, 0, 0, 0.0f, 1.0f, 0.0f);
var aspect_ratio = Width / (float)Height;
projection = Matrix4.CreatePerspectiveFieldOfView(MathHelper.PiOver4, aspect_ratio, 1, 512);
GL.MatrixMode(MatrixMode.Projection);
GL.LoadMatrix(ref projection);
GL.MatrixMode(MatrixMode.Modelview);
GL.LoadMatrix(ref modelview);
GL.Rotate(angleY, 1.0f, 0, 0);
GL.Rotate(angleX, 0, 1.0f, 0);
GL.EnableClientState(ArrayCap.VertexArray);
GL.BindBuffer(BufferTarget.ArrayBuffer, VBOid[0]);
GL.Color3(Color.Yellow);
GL.VertexPointer(3, VertexPointerType.Float, Vector3.SizeInBytes, new IntPtr(0));
GL.DrawArrays(PrimitiveType.Triangles, 0, data.Length);
GL.BindBuffer(BufferTarget.ArrayBuffer, 0);
GL.DisableClientState(ArrayCap.VertexArray);
//GL.Color3(Color.Yellow);
//GL.PolygonMode(MaterialFace.Front, PolygonMode.Fill);
//GL.Begin(PrimitiveType.Triangles);
//for (int i = 0; i < this.md.mesh.Count; i++)
//{
// GL.Normal3(this.md.mesh[i].normal);
// GL.Vertex3(this.md.mesh[i].vertices[0]);
// GL.Vertex3(this.md.mesh[i].vertices[1]);
// GL.Vertex3(this.md.mesh[i].vertices[2]);
//}
//GL.End();
//GL.EndList();
glControl.SwapBuffers();
Frame_label.Text = "Frame: " + frameNum++;
}
}
If something doesn't seem right, then it probably isn't. I seriously questioned my understanding of opengl and spent hours looking at this. However it was just a simple error of forgetting to iterate a count variable in a for loop to transfer the mesh from one object to another. Each triangle had identical vertices! Always expect the unexpected when it comes to debugging!

error c0000: syntax error, unexpected '?' at token '?'

Alright I searched other peoples questions and could not find a solution to my problem. I am using OpenTK in C# and GLSL 330. It is producing the error message
error c0000: syntax error, unexpected '?' at token '?'
For some reason it doesn't like something I'm doing. So, here is my code I hope someone can tell
me what I'm doing wrong.
public static string vertexShaderSource = #"
#version 330
uniform mat4 pvm;
in vec4 Position;
in vec2 texCoord;
out vec2 texCoordV;
void main()
{
texCoordV = texCoord;
gl_Position = Position * pvm;
}";
public static string fragmentShaderSource = #"
#version 330
in vec2 texCoordV;
out vec4 colorOut;
void main()
{
colorOut = vec4(texCoord, 0.0, 0.0);
}";
public void Initalize()
{
style = GUI_Skin.styles[0];
vertices = new Vector3[6];
vertices[0] = new Vector3(0, 0, 0f);
vertices[1] = new Vector3(100, 0, 0f);
vertices[2] = new Vector3(0, 100, 0f);
vertices[3] = new Vector3(100, 0, 0f);
vertices[4] = new Vector3(0, 100, 0f);
vertices[5] = new Vector3(100, 100, 0f);
GL.GenBuffers(1, out vertHandle);
GL.BindBuffer(BufferTarget.ArrayBuffer, vertHandle);
GL.BufferData<Vector3>(BufferTarget.ArrayBuffer,
new IntPtr(vertices.Length * Vector3.SizeInBytes),
vertices, BufferUsageHint.StaticDraw);
texCoords = new Vector2[6];
texCoords[0] = new Vector2(0,0);
texCoords[1] = new Vector2(1, 0);
texCoords[2] = new Vector2(0, 1);
texCoords[3] = new Vector2(1, 0);
texCoords[4] = new Vector2(0, 1);
texCoords[5] = new Vector2(1, 1);
GL.GenBuffers(1, out texHandle);
GL.BindBuffer(BufferTarget.ArrayBuffer, texHandle);
GL.BufferData<Vector2>(BufferTarget.ArrayBuffer,
new IntPtr(texCoords.Length * Vector2.SizeInBytes),
texCoords, BufferUsageHint.StaticDraw);
}
public void Draw()
{
GL.EnableVertexAttribArray(vertHandle);
GL.BindBuffer(BufferTarget.ArrayBuffer, vertHandle);
GL.VertexAttribPointer(0, 3, VertexAttribPointerType.Float, false, Vector3.SizeInBytes, 0);
GL.EnableVertexAttribArray(texHandle);
GL.BindBuffer(BufferTarget.ArrayBuffer, texHandle);
GL.VertexAttribPointer(0, 2, VertexAttribPointerType.Float, false, Vector2.SizeInBytes, 0);
GL.DrawArrays(PrimitiveType.Triangles, 0, 6);
GL.DisableVertexAttribArray(vertHandle);
GL.DisableVertexAttribArray(texHandle);
}
Alright so the issues have been fixed. Thanks to the helpful comments above.
Lets start with the shader. The # symbol before the string declaration had to be removed and after every line \n had to be inserted. Also, I was calling transpose when I draw with the shader. Which could be fixed by changing the order of matrices.
public static void Run()
{
int uniformLocation = GL.GetUniformLocation(shaderProgramHandle, "pvm");
Matrix4 mat;
GL.GetFloat(GetPName.ProjectionMatrix, out mat);
GL.UniformMatrix4(uniformLocation, false, ref mat);
GL.UseProgram(shaderProgramHandle);
}
I changed from GL.UniformMatrix4(uniformLocation, true, ref mat); to GL.UniformMatrix4(uniformLocation, false, ref mat); and in the shader itself the order of gl_Position was changed from Position * pvm; to pvm * Position;
public static string vertexShaderSource = "#version 330\n" +
"uniform mat4 pvm;\n" +
"in vec4 Position;\n" +
"in vec2 texCoord;\n" +
"out vec2 texCoordV;\n" +
"void main()\n" +
"{\n" +
"texCoordV = texCoord;\n" +
"gl_Position = pvm * Position;\n" +
"}\n";
public static string fragmentShaderSource = "#version 330\n" +
"in vec2 texCoordV;\n" +
"out vec4 colorOut;" +
"void main()\n" +
"{\n" +
"colorOut = vec4(texCoordV, 0.0, 0.0);\n" +
"}\n" ;
After this was fixed I was getting an error where the rendering surface went white. The error was located within the Draw() function. Basically I wasn't assigning the array locations properly.
public void Draw()
{
GL.EnableVertexAttribArray(0);
GL.BindBuffer(BufferTarget.ArrayBuffer, vertHandle);
GL.VertexAttribPointer(0, 3, VertexAttribPointerType.Float, false, Vector3.SizeInBytes, 0);
GL.EnableVertexAttribArray(1);
GL.BindBuffer(BufferTarget.ArrayBuffer, texHandle);
GL.VertexAttribPointer(1, 2, VertexAttribPointerType.Float, false, Vector2.SizeInBytes, 0);
GL.DrawArrays(PrimitiveType.Triangles, 0, 6);
GL.DisableVertexAttribArray(0);
GL.DisableVertexAttribArray(1);
}

Draw texture with shader

I want to draw a texture in my shader but get an exception (see below).
I have following code:
int vertexArray;
//Pointer to Buffers
int vertexBuffer;
int colorBuffer;
int coordBuffer;
int texUniform; //Pointer to Uniform
int texture; //Pointer to Texture
Init
GL.Enable(EnableCap.Texture2D);
texture = LoadPNG("Resources\\Test.png");
//...
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMagFilter, (float)All.Nearest);
GL.TexParameter(TextureTarget.Texture2D, TextureParameterName.TextureMinFilter, (float)All.Nearest);
GL.Hint(HintTarget.PerspectiveCorrectionHint, HintMode.Nicest);
vertexArray = GL.GenVertexArray();
GL.BindVertexArray(vertexArray);
float[] TexCoords = new float[] {
0.0f, 0.0f,
1.0f, 0.0f,
0.0f, 1.0f,
}; //(Array.Length = 2*3)
//Arrays for Vertex (3*3) and Color (4*3)
//GenBuffer, BindBuffer and BufferData for Color and Vertex
coordBuffer = GL.GenBuffer();
GL.BindBuffer(BufferTarget.TextureBuffer, coordBuffer);
GL.BufferData(BufferTarget.TextureBuffer, (IntPtr)(sizeof(float) * TexCoords.Length), TexCoords, BufferUsageHint.StaticDraw);
//Load shader
texUniform = GL.GetUniformLocation(shaderProgram, "tex");
GL.Uniform1(texUniform, 0);
GL.ActiveTexture(TextureUnit.Texture0);
Draw
GL.UseProgram(shaderProgram);
GL.BindTexture(TextureTarget.Texture2D, texture);
GL.EnableVertexAttribArray(0);
GL.BindBuffer(BufferTarget.ArrayBuffer, vertexBuffer);
GL.VertexAttribPointer(0, 3, VertexAttribPointerType.Float, false, 0, 0);
GL.EnableClientState(ArrayCap.VertexArray);
GL.EnableVertexAttribArray(1);
GL.BindBuffer(BufferTarget.ArrayBuffer, colorBuffer);
GL.VertexAttribPointer(1, 4, VertexAttribPointerType.Float, false, 0, 0);
GL.EnableClientState(ArrayCap.ColorArray);
GL.BindBuffer(BufferTarget.TextureBuffer, coordBuffer);
GL.TexCoordPointer(2, TexCoordPointerType.Float, Vector2.SizeInBytes, 0);
GL.EnableClientState(ArrayCap.TextureCoordArray);
GL.DrawArrays(PrimitiveType.Triangles, 0, 6); //<------ Exception
GL.DisableVertexAttribArray(0);
GL.DisableVertexAttribArray(1);
I get a System.AccessViolationException at GL.DrawArrays(...);. I suspect that i haven't loaded a buffer correctly or used a pointer in an incorrect way. The exception is caused by changes i did to get a texture with texture coordinates into the shader, that means vertex and color buffer are working.
I'm not sure what i am doing wrong. I tried different things with the shader but it seems it doesn't matter what i am doing with the shader...
At my last try:
Vertex Shader
#version 330 core
layout(location = 0) in vec3 position;
layout(location = 1) in vec4 color;
layout(location = 2) in vec2 texCoord;
out vec4 vColor;
out vec2 texCoords[];
void main(){
gl_Position = vec4(position, 1.0);
texCoords[0] = texCoord;
vColor = color;
}
Fragment Shader
#version 330 core
in vec4 vColor;
in vec2 texCoords[];
uniform sampler2D tex;
out vec4 fColor;
void main(void)
{
//fColor = vColor;
fColor = texture2D(Texture0, texCoords[0].st);
}
GetShaderInfoLog and GetProgramInfoLog do not return any errors when i comment GL.DrawArrays(...) and run the application.
What is wrong with my code?
Do not enable client state vertex arrays.
Replace the following:
GL.EnableClientState(ArrayCap.VertexArray);
...
GL.EnableClientState(ArrayCap.ColorArray);
...
GL.EnableClientState(ArrayCap.TextureCoordArray);
With:
GL.EnableVertexAttribArray(0);
...
GL.EnableVertexAttribArray(1);
...
GL.EnableVertexAttribArray(2);
At present, you are telling GL to source vertex attributes from glVertexPointer (...), glColorPointer (...) and glTexCoordPointer (...), none of which you actually have setup.
You might be able to get away with enabling the client state: ArrayCap.VertexArray because many drivers alias that to attribute 0, but the others are a recipe for disaster. Nevertheless, until you remove the EnableClientState (...) calls you are going to continue crashing.
Update:
I missed something in your texture coordinate setup...
You also need to replace this line:
GL.TexCoordPointer(2, TexCoordPointerType.Float, Vector2.SizeInBytes, 0);
With this:
GL.VertexAttribPointer(2, 2, VertexAttribPointerType.Float, false, 0, 0);

trouble with showing texture Tao-framework/OpenGl

I am using Tao Framework to work with OpenGl. I`m trying to load a texture and show it on the form. Image seems to be load correctly (texture id is generated and no errors occure) but it is not shown correctly.
Here is my code for loading texture
public static class TextureManager
{
static TextureManager()
{
Il.ilInit();
Il.ilEnable(Il.IL_ORIGIN_SET);
}
public static int LoadTexture(string url)
{
int texObject = -1;
int imageId;
Il.ilGenImages(1, out imageId);
Il.ilBindImage(imageId);
if (Il.ilLoadImage(url))
{
int width = Il.ilGetInteger(Il.IL_IMAGE_WIDTH);
int height = Il.ilGetInteger(Il.IL_IMAGE_HEIGHT);
Gl.glGenTextures(1, out texObject);
Gl.glPixelStorei(Gl.GL_UNPACK_ALIGNMENT, 1);
Gl.glBindTexture(Gl.GL_TEXTURE_2D, texObject);
Gl.glTexParameteri(Gl.GL_TEXTURE_2D, Gl.GL_TEXTURE_WRAP_S, Gl.GL_REPEAT);
Gl.glTexParameteri(Gl.GL_TEXTURE_2D, Gl.GL_TEXTURE_WRAP_T, Gl.GL_REPEAT);
Gl.glTexParameteri(Gl.GL_TEXTURE_2D, Gl.GL_TEXTURE_MAG_FILTER, Gl.GL_LINEAR);
Gl.glTexParameteri(Gl.GL_TEXTURE_2D, Gl.GL_TEXTURE_MIN_FILTER, Gl.GL_LINEAR);
Gl.glTexEnvf(Gl.GL_TEXTURE_ENV, Gl.GL_TEXTURE_ENV_MODE, Gl.GL_REPLACE);
Gl.glTexImage2D(Gl.GL_TEXTURE_2D, 0, Gl.GL_RGB, width, height, 0, Gl.GL_RGB, Gl.GL_UNSIGNED_BYTE, Il.ilGetData());
Il.ilDeleteImages(1, ref imageId);
}
return texObject;
}
}
And code for drawing it:
Gl.glClear(Gl.GL_COLOR_BUFFER_BIT | Gl.GL_DEPTH_BUFFER_BIT);
Gl.glClearColor(255, 255, 255, 1);
Gl.glLoadIdentity();
Gl.glEnable(Gl.GL_TEXTURE_2D);
Gl.glBindTexture(Gl.GL_TEXTURE_2D, mGlTextureObject);
Gl.glPushMatrix();
Gl.glTranslated(0, -1, -10);
Gl.glRotated(rot, 0, 1, 0);
Gl.glBegin(Gl.GL_QUADS);
Gl.glNormal3f(0, 0, 1);
Gl.glTexCoord2f(0, 0); Gl.glVertex3d(0, 0, 0);
Gl.glTexCoord2f(1, 0); Gl.glVertex3d(1, 0, 0);
Gl.glTexCoord2f(1, 1); Gl.glVertex3d(1, 1, 0);
Gl.glTexCoord2f(0, 1); Gl.glVertex3d(0, 1, 0);
Gl.glEnd();
Gl.glPopMatrix();
Gl.glDisable(Gl.GL_TEXTURE_2D);
AnT.Invalidate();
The form is just blank. But if I enable lightning then here what is showed:
The image I am loading is a simple bmp image 100x100 created in Paint.
The problem appeared because the image was in incorrect size. Size of images should be 64x64, 128x128 or 256x256.
Changed the size to 128x128 and everything worked fine.

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