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OpenGL Open a 3.2 OPENGL context or superior

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[b]Hi all,[/b]

just 2 questions
here is my code, I use the correct method to open [b]a context "core profile"?[/b]
I have a yellow texture, please consider I clearly see my yellow triangle when I'm context <3.2 and if I open a context> = 3.2 my texture disappears (the triangle become black)

thank you in advance for your answers

my code :
[CODE]
#define WIDTH 800
#define HEIGHT 600
#define NBP 32
#define MAJOR 3 // for creating context opengl MAJOR VERSION TRY MAJOR = 3
#define MINOR 1 // for creating context opengl MINOR VERSION TRY MINOR >= 2
#define FULLSCREEN false
#define PI 3.14159265
#define TEXTURESIZE 256 * 256 * 3
#include <Windows.h>
#include <math.h>
#include <stdio.h> // fopen, fread, fclose
#include "GL3\gl3.h"

class mat4
{
public:
float m[16];
const float* GetMatriceOpengl() const;
void mat4::Identity();
};
#ifdef __cplusplus
extern "C" {
#endif
GLAPI void APIENTRY glClearColor (GLfloat red, GLfloat green, GLfloat blue, GLfloat alpha);
GLAPI void APIENTRY glClear (GLbitfield mask);
GLAPI const GLubyte * APIENTRY glGetString (GLenum name);
GLAPI void APIENTRY glEnable (GLenum cap);
GLAPI void APIENTRY glDrawArrays (GLenum mode, GLint first, GLsizei count);
GLAPI void APIENTRY glDrawElements (GLenum mode, GLsizei count, GLenum type, const GLvoid *indices);
GLAPI void APIENTRY glDisable (GLenum cap);
GLAPI void APIENTRY glViewport (GLint x, GLint y, GLsizei width, GLsizei height);
GLAPI void APIENTRY glBindTexture (GLenum target, GLuint texture);
GLAPI void APIENTRY glGenTextures (GLsizei n, GLuint *textures);
GLAPI void APIENTRY glTexImage2D (GLenum target, GLint level, GLint internalformat, GLsizei width, GLsizei height, GLint border, GLenum format, GLenum type, const GLvoid *pixels);
GLAPI void APIENTRY glTexParameteri (GLenum target, GLenum pname, GLint param);
GLAPI void APIENTRY glGetIntegerv (GLenum pname, GLint *params);
#ifdef __cplusplus
}
#endif
PFNGLCREATEPROGRAMPROC glCreateProgram = NULL;
PFNGLUNIFORMMATRIX4FVPROC glUniformMatrix4fv = NULL;
PFNGLGENVERTEXARRAYSPROC glGenVertexArrays = NULL;
PFNGLBINDVERTEXARRAYPROC glBindVertexArray = NULL;
PFNGLGENBUFFERSPROC glGenBuffers = NULL;
PFNGLBINDBUFFERPROC glBindBuffer = NULL;
PFNGLBUFFERDATAPROC glBufferData = NULL;
PFNGLVERTEXATTRIBPOINTERPROC glVertexAttribPointer = NULL;
PFNGLENABLEVERTEXATTRIBARRAYPROC glEnableVertexAttribArray = NULL;
PFNGLCREATESHADERPROC glCreateShader = NULL;
PFNGLSHADERSOURCEPROC glShaderSource = NULL;
PFNGLCOMPILESHADERPROC glCompileShader = NULL;
PFNGLBINDATTRIBLOCATIONPROC glBindAttribLocation = NULL;
PFNGLATTACHSHADERPROC glAttachShader = NULL;
PFNGLLINKPROGRAMPROC glLinkProgram = NULL;
PFNGLUSEPROGRAMPROC glUseProgram = NULL;
PFNGLGETUNIFORMLOCATIONPROC glGetUniformLocation = NULL;
PFNGLGETSHADERIVPROC glGetShaderiv = NULL;
PFNGLGETPROGRAMIVPROC glGetProgramiv = NULL;
PFNGLGETSHADERINFOLOGPROC glGetShaderInfoLog = NULL;
PFNGLGETPROGRAMINFOLOGPROC glGetProgramInfoLog = NULL;
PFNGLACTIVETEXTUREPROC glActiveTexture = NULL;
PFNGLUNIFORM1IPROC glUniform1i = NULL;
PFNGLGETSTRINGIPROC glGetStringi = NULL;
unsigned int vao;
unsigned int vbo[2];
float incx, incy, incz;
GLuint vshader;
GLuint fshader;
GLuint program;
char source1[1024*1024*4];
char source2[1024*1024*4];
short taillex, tailley;
unsigned char *data = new unsigned char[TEXTURESIZE];
GLuint texture;
GLuint tex;
mat4 pmatrix;
mat4 mmatrix;
float A, B, C, D, E, F, AD, BD;
LRESULT CALLBACK WndProc( HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam );
float triangle[] = { // pos // Map
-1.0f, 1.0f, 1.0f, 0.0f, 0.0f,
-1.0f, -1.0f, 1.0f, 0.0f, 4.0f,
1.0f, -1.0f, 1.0f, 4.0f, 4.0f };
GLuint indicetriangle[] = { 0,1,2 };
#define WGL_CONTEXT_MAJOR_VERSION_ARB 0x2091
#define WGL_CONTEXT_MINOR_VERSION_ARB 0x2092
#define WGL_CONTEXT_PROFILE_MASK_ARB 0x9126
#define WGL_CONTEXT_CORE_PROFILE_BIT_ARB 0x00000001
int attriblist[] = { WGL_CONTEXT_MAJOR_VERSION_ARB, MAJOR, WGL_CONTEXT_MINOR_VERSION_ARB, MINOR, WGL_CONTEXT_PROFILE_MASK_ARB, WGL_CONTEXT_CORE_PROFILE_BIT_ARB, 0, 0 };
HGLRC wglCreateContextAttribsARB(HDC hDC, HGLRC hShareContext, const int *attribList)
{
typedef HGLRC (APIENTRY * PFNWGLCREATECONTEXTATTRIBSARBPROC)(HDC hDC, HGLRC hShareContext, const int *attribList);
static PFNWGLCREATECONTEXTATTRIBSARBPROC pfnCreateContextAttribsARB = 0;

HGLRC hContext = 0;
HGLRC hCurrentContext = wglGetCurrentContext();

if (!hCurrentContext)
{
if (!(hCurrentContext = wglCreateContext(hDC)))
return 0;
if (!wglMakeCurrent(hDC, hCurrentContext))
{
wglDeleteContext(hCurrentContext);
return 0;
}
pfnCreateContextAttribsARB = reinterpret_cast<PFNWGLCREATECONTEXTATTRIBSARBPROC>(wglGetProcAddress("wglCreateContextAttribsARB"));

if (pfnCreateContextAttribsARB)
hContext = pfnCreateContextAttribsARB(hDC, hShareContext, attribList);
wglMakeCurrent(hDC, 0);
wglDeleteContext(hCurrentContext);
}
else
{
if (!wglMakeCurrent(hDC, hCurrentContext))
return 0;
pfnCreateContextAttribsARB = reinterpret_cast<PFNWGLCREATECONTEXTATTRIBSARBPROC>(wglGetProcAddress("wglCreateContextAttribsARB"));
if (pfnCreateContextAttribsARB)
hContext = pfnCreateContextAttribsARB(hDC, hShareContext, attribList);
}
return hContext;
}
const float* mat4::GetMatriceOpengl() const
{
return &m[0];
}
void mat4::Identity()
{
memset(m, 0, sizeof(float)*16);
m[0] = m[5] = m[10] = m[15] = 1.0f;
}
mat4 MultMatrice(mat4* m, mat4 *n)
{
static mat4 mat;
mat.m[0] = m->m[0]*n->m[0] + m->m[4]*n->m[1] + m->m[8]*n->m[2] + m->m[12]*n->m[3];
mat.m[1] = m->m[1]*n->m[0] + m->m[5]*n->m[1] + m->m[9]*n->m[2] + m->m[13]*n->m[3];
mat.m[2] = m->m[2]*n->m[0] + m->m[6]*n->m[1] + m->m[10]*n->m[2] + m->m[14]*n->m[3];
mat.m[3] = m->m[3]*n->m[0] + m->m[7]*n->m[1] + m->m[11]*n->m[2] + m->m[15]*n->m[3];
mat.m[4] = m->m[0]*n->m[4] + m->m[4]*n->m[5] + m->m[8]*n->m[6] + m->m[12]*n->m[7];
mat.m[5] = m->m[1]*n->m[4] + m->m[5]*n->m[5] + m->m[9]*n->m[6] + m->m[13]*n->m[7];
mat.m[6] = m->m[2]*n->m[4] + m->m[6]*n->m[5] + m->m[10]*n->m[6] + m->m[14]*n->m[7];
mat.m[7] = m->m[3]*n->m[4] + m->m[7]*n->m[5] + m->m[11]*n->m[6] + m->m[15]*n->m[7];
mat.m[8] = m->m[0]*n->m[8] + m->m[4]*n->m[9] + m->m[8]*n->m[10] + m->m[12]*n->m[11];
mat.m[9] = m->m[1]*n->m[8] + m->m[5]*n->m[9] + m->m[9]*n->m[10] + m->m[13]*n->m[11];
mat.m[10] = m->m[2]*n->m[8] + m->m[6]*n->m[9] + m->m[10]*n->m[10] + m->m[14]*n->m[11];
mat.m[11] = m->m[3]*n->m[8] + m->m[7]*n->m[9] + m->m[11]*n->m[10] + m->m[15]*n->m[11];
mat.m[12] = m->m[0]*n->m[12] + m->m[4]*n->m[13] + m->m[8]*n->m[14] + m->m[12]*n->m[15];
mat.m[13] = m->m[1]*n->m[12] + m->m[5]*n->m[13] + m->m[9]*n->m[14] + m->m[13]*n->m[15];
mat.m[14] = m->m[2]*n->m[12] + m->m[6]*n->m[13] + m->m[10]*n->m[14] + m->m[14]*n->m[15];
mat.m[15] = m->m[3]*n->m[12] + m->m[7]*n->m[13] + m->m[11]*n->m[14] + m->m[15]*n->m[15];

return mat;
}
void glTranslate(mat4 *mat, float x, float y, float z)
{
static mat4 m;
m.m[0] = m.m[5] = m.m[10] = m.m[15] = 1.0f;
m.m[1] = m.m[2] = m.m[3] = m.m[4] = m.m[6] = m.m[7] = m.m[8] = m.m[9] = m.m[11] = 0.0f;
m.m[12] = x;
m.m[13] = y;
m.m[14] = z;
*mat = MultMatrice(mat,&m);
}
void glPerspective( mat4 &mat, float fovy, float ratio, float znear, float zfar )
{
static float ymax, xmax;
static float temp, temp4;
ymax = float(znear * tanf(float(fovy * PI / 360.0f)));
xmax = ymax * ratio;
temp = znear + znear;
temp4 = zfar - znear;
mat.m[0] = znear / xmax;
mat.m[1] =mat.m[2] =mat.m[3] =mat.m[4] =mat.m[6] =mat.m[7] =mat.m[8] =mat.m[9] =mat.m[12] =mat.m[13] =mat.m[15] = 0.0;
mat.m[5] = znear / ymax;
mat.m[10] = (-zfar - znear) / temp4;
mat.m[11] = -1.0;
mat.m[14] = (-temp * zfar) / temp4;
}
void LoadFile(char *name, char *buffer)
{
FILE *hfile = fopen(name, "rb");
if (hfile)
{
fread(buffer, 1, 10000, hfile);
fclose(hfile);
}
}
void Init()
{
glCreateProgram = (PFNGLCREATEPROGRAMPROC)wglGetProcAddress("glCreateProgram");
glUniformMatrix4fv = (PFNGLUNIFORMMATRIX4FVPROC)wglGetProcAddress("glUniformMatrix4fv");
glGenVertexArrays = (PFNGLGENVERTEXARRAYSPROC)wglGetProcAddress("glGenVertexArrays");
glBindVertexArray = (PFNGLBINDVERTEXARRAYPROC)wglGetProcAddress("glBindVertexArray");
glGenBuffers = (PFNGLGENBUFFERSPROC)wglGetProcAddress("glGenBuffers");
glBindBuffer = (PFNGLBINDBUFFERPROC)wglGetProcAddress("glBindBuffer");
glBufferData = (PFNGLBUFFERDATAPROC)wglGetProcAddress("glBufferData");
glVertexAttribPointer = (PFNGLVERTEXATTRIBPOINTERPROC)wglGetProcAddress("glVertexAttribPointer");
glEnableVertexAttribArray = (PFNGLENABLEVERTEXATTRIBARRAYPROC)wglGetProcAddress("glEnableVertexAttribArray");
glCreateShader = (PFNGLCREATESHADERPROC)wglGetProcAddress("glCreateShader");
glShaderSource = (PFNGLSHADERSOURCEPROC)wglGetProcAddress("glShaderSource");
glCompileShader = (PFNGLCOMPILESHADERPROC)wglGetProcAddress("glCompileShader");
glBindAttribLocation = (PFNGLBINDATTRIBLOCATIONPROC)wglGetProcAddress("glBindAttribLocation");
glAttachShader = (PFNGLATTACHSHADERPROC)wglGetProcAddress("glAttachShader");
glLinkProgram = (PFNGLLINKPROGRAMPROC)wglGetProcAddress("glLinkProgram");
glUseProgram = (PFNGLUSEPROGRAMPROC)wglGetProcAddress("glUseProgram");
glGetUniformLocation = (PFNGLGETUNIFORMLOCATIONPROC)wglGetProcAddress("glGetUniformLocation");
glGetShaderiv = (PFNGLGETSHADERIVPROC)wglGetProcAddress("glGetShaderiv");
glGetProgramiv = (PFNGLGETPROGRAMIVPROC)wglGetProcAddress("glGetProgramiv");
glGetShaderInfoLog = (PFNGLGETSHADERINFOLOGPROC)wglGetProcAddress("glGetShaderInfoLog");
glGetProgramInfoLog = (PFNGLGETPROGRAMINFOLOGPROC)wglGetProcAddress("glGetProgramInfoLog");
glActiveTexture = (PFNGLACTIVETEXTUREPROC)wglGetProcAddress("glActiveTexture");
glUniform1i = (PFNGLUNIFORM1IPROC)wglGetProcAddress("glUniform1i");
glGetStringi = (PFNGLGETSTRINGIPROC)wglGetProcAddress("glGetStringi");
glGenVertexArrays(1, &vao);
glBindVertexArray(vao);
glGenBuffers(2, &vbo[0]);
glBindBuffer(GL_ARRAY_BUFFER, vbo[0]);
glBufferData(GL_ARRAY_BUFFER, sizeof(triangle), triangle, GL_STATIC_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, vbo[1]);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indicetriangle), indicetriangle, GL_STATIC_DRAW);
glVertexAttribPointer((GLuint)0, 3, GL_FLOAT, GL_FALSE, 20, 0);
glVertexAttribPointer((GLuint)1, 2, GL_FLOAT, GL_FALSE, 20, (void*)12);
glEnableVertexAttribArray(0);
glEnableVertexAttribArray(1);
glBindVertexArray(0);
const char *src = source1;
vshader = glCreateShader(GL_VERTEX_SHADER);
fshader = glCreateShader(GL_FRAGMENT_SHADER);
LoadFile("vert.txt", source1);
glShaderSource(vshader, 1, &src, NULL);
glCompileShader(vshader);
LoadFile("frag.txt", source2);
src = source2;
glShaderSource(fshader, 1, &src, NULL);
glCompileShader(fshader);
program = glCreateProgram();
glAttachShader(program, vshader);
glAttachShader(program, fshader);
// glBindAttribLocation(program,0, "vert");
// glBindAttribLocation(program,1, "texture");
glLinkProgram(program);
tex = glGetUniformLocation(program, "gsample");

taillex = 256;
tailley = 256;

unsigned char *p = data;
for (int t = 0 ; t < taillex*tailley ; t++) // i create a yellow texture just for testing
*p++ = 255, *p++ = 255, *p++ = 0;
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glTexImage2D(GL_TEXTURE_2D , 0 , 3 , taillex , tailley , 0 , GL_RGB , GL_UNSIGNED_BYTE , data);
glTexParameteri(GL_TEXTURE_2D , GL_TEXTURE_MIN_FILTER , GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D , GL_TEXTURE_MAG_FILTER , GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D , GL_TEXTURE_WRAP_S , GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D , GL_TEXTURE_WRAP_T , GL_REPEAT);
glBindTexture(GL_TEXTURE_2D, 0);
};
int MainSub()
{
glUseProgram(program);
glEnable(GL_CULL_FACE);
glEnable(GL_DEPTH_TEST);
glClearColor(0.0f,0.2f,0.4f,1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
mmatrix.Identity();
incz = -3.5f;
glTranslate(&mmatrix, incx, incy, incz);
glUniformMatrix4fv(glGetUniformLocation(program, "projectionmatrix"), 1, GL_FALSE, pmatrix.GetMatriceOpengl());
glUniformMatrix4fv(glGetUniformLocation(program, "modelmatrix"), 1, GL_FALSE, mmatrix.GetMatriceOpengl());
glBindVertexArray(vao);
glUniform1i(tex, 0);
glActiveTexture(GL_TEXTURE0);
glBindTexture(GL_TEXTURE_2D,texture);
//glDrawArrays(GL_TRIANGLES, 0, 3); // draw first object
glDrawElements(GL_TRIANGLES, 3, GL_UNSIGNED_INT,0);
glBindVertexArray(0);
glUseProgram(0);
return true;
}
int WINAPI WinMain(HINSTANCE hinst,HINSTANCE hprev, LPSTR cmdline, int cmdshow)
{
static MSG msg;
HWND hwnd;
HDC hdc;
HGLRC hrc;
WNDCLASSEX wnd;
DWORD style;
DWORD exstyle;

wnd.cbSize = sizeof( WNDCLASSEX ) ;
wnd.style = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
wnd.lpfnWndProc = WndProc;
wnd.hInstance = hinst;
wnd.hCursor = LoadCursor( NULL, IDC_HAND );
wnd.hIcon = LoadIcon(NULL, IDI_ASTERISK);
wnd.hIconSm = LoadIcon(NULL, IDI_WINLOGO);
wnd.hbrBackground = 0;
wnd.lpszMenuName = 0;
wnd.cbClsExtra = 0;
wnd.cbWndExtra = 0;
wnd.lpszClassName = "wc";
RegisterClassEx(&wnd);

if (FULLSCREEN)
{
DEVMODE dm;
memset(&dm, 0, sizeof(dm));
dm.dmSize = sizeof(dm);
dm.dmPelsWidth = WIDTH;
dm.dmPelsHeight = HEIGHT;
dm.dmBitsPerPel = NBP;
dm.dmFields = DM_BITSPERPEL | DM_PELSWIDTH | DM_PELSHEIGHT;
ChangeDisplaySettings(&dm, CDS_FULLSCREEN);
style = WS_POPUP;
exstyle = WS_EX_APPWINDOW;
ShowCursor(FALSE);
}
else
{
style = WS_OVERLAPPEDWINDOW;
exstyle = WS_EX_APPWINDOW | WS_EX_WINDOWEDGE;
}
RECT rc = { 0, 0, WIDTH, HEIGHT };
AdjustWindowRectEx( &rc, style, false, exstyle );
hwnd = CreateWindowEx( exstyle, "wc", "MyWindows", style, 0, 0, rc.right - rc.left, rc.bottom - rc.top, NULL, NULL, hinst, NULL );
static PIXELFORMATDESCRIPTOR pfd =
{
sizeof(PIXELFORMATDESCRIPTOR),
1,
PFD_DRAW_TO_WINDOW | PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER,
PFD_TYPE_RGBA,
NBP,
0, 0, 0, 0, 0, 0,
0,
0,
0,
0, 0, 0, 0,
16, // 16Bit Z-Buffer (Depth Buffer)
0,
0,
PFD_MAIN_PLANE,
0,
0, 0, 0
};
hdc = GetDC(hwnd);
unsigned int pixelformat = ChoosePixelFormat(hdc, &pfd);
SetPixelFormat(hdc, pixelformat, &pfd);
if (MAJOR < 3) // open Standard Context
hrc = wglCreateContext(hdc);
else
hrc = wglCreateContextAttribsARB(hdc, 0, attriblist); // open à New Core Context
wglMakeCurrent(hdc, hrc);
ShowWindow( hwnd, cmdshow );

Init();
const GLubyte *version = glGetString(GL_VERSION);
MessageBox(NULL,(char *)version ,"Opengl Version",MB_OK|MB_ICONEXCLAMATION);
while( msg.message != WM_QUIT )
{
if( PeekMessage( &msg, 0, 0, 0, PM_REMOVE ) )
{
TranslateMessage( &msg );
DispatchMessage( &msg );
}
MainSub();
SwapBuffers(hdc); // Double Buffer
}

if (FULLSCREEN)
{
ChangeDisplaySettings(NULL,0);
ShowCursor(TRUE);
}
wglMakeCurrent(NULL,NULL);
wglDeleteContext(hrc);
hrc = 0;
ReleaseDC(hwnd,hdc);
hdc = 0;
DestroyWindow(hwnd);
hwnd = 0;
UnregisterClass("wclasse",hinst);
delete [] data;
return static_cast<int>( msg.wParam );
}
LRESULT CALLBACK WndProc( HWND hwnd, UINT message, WPARAM wparam, LPARAM lparam )
{
static short width;
static short height;
switch( message )
{

case WM_DESTROY:
PostQuitMessage( 0 );
break;
case WM_SIZE:
width= LOWORD(lparam);
height = HIWORD(lparam);
if ( height == 0 )
height = 1;
glViewport(0, 0, width, height);
glPerspective( pmatrix, 45.0f, (GLfloat)width/(GLfloat)height, 0.1f, 100.0f );
break;
default:
return DefWindowProc( hwnd, message, wparam, lparam );
}
return 0;
}
[/CODE]

Vertex shader :
[CODE]
#version 330
layout(location = 0)in vec3 vertex;
layout(location = 1)in vec2 texture;
out vec2 _texture;
uniform mat4 projectionmatrix;
uniform mat4 modelmatrix;
void main(void)
{
mat4 mvpMatrix = projectionmatrix * modelmatrix;
_texture = texture;
gl_Position = mvpMatrix * vec4(vertex, 1.0);
}
[/CODE]

Fragment Shader :
[CODE]
#version 330
in vec2 _texture;
out vec4 fragcolor;
uniform sampler2D gsample;
void main(void)
{
fragcolor = texture2D(gsample, _texture);
}
[/CODE]

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#1 guideline: In debug mode, after each call to a glXXX function, call http://www.opengl.org/sdk/docs/man/xhtml/glGetError.xml . With OpenGL, you can never be sure, and you must at least detect the few problems OpenGL is capable of reporting. I call the following function after each glXXX call:
[code]

int Graphics::CheckErrors(const char *hintOperation)
{
#ifndef OPTIMIZED_RELEASE
GLenum returnError = 0;
GLenum error = GL_NO_ERROR+1;
int maxIters = 100; // Arbitrarily cap the number of iterations to avoid infinite loop on buggy drivers.
while(error != GL_NO_ERROR && maxIters-- > 0)
{
error = glGetError();
if (error != GL_NO_ERROR)
{
LOGW("glGetError: \"%s\" failed: Error %s (0x%X) received!\n", hintOperation, GetGLErrorString(error), (int)error);
returnError = error;
}
}
return returnError;
#else
return 0;
#endif
}
[/code]
Then I do something along the lines of
[code]
#define GL_CALL(x) { x; Graphics::CheckErrors(#x); }

GL_CALL(glBindVertexArray(vb->vertexArrayObject));
[/code]

#2: Use [url="http://www.gremedy.com/"]gDEBugger[/url] to peek inside your application execution. This allows you to verify GL server side state and confirm that everything is as you expected.

I find that the combination of #1 and #2 has allowed me to get past all the problems I've encountered, without having to spend days scratching my head.

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thanks Clb,

I delete all the verification that the source is as short as possible.

but it's true that I should use glGetError but even with use are
this does not solve my problem :-(

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With all the glGetError checks in place, does any of them report any errors? What did gDEBugger say?

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I'm an idiot

in fact I did not put [b]glGetError everywhere[/b], I thought one was enough to know if opengl met an error.
[b]I was in my wrong :-([/b]
my problem of texture came from :

glTexImage2D (GL_TEXTURE_2D, 0, [b]3[/b], taillex, tailley, 0, GL_RGB, GL_UNSIGNED_BYTE, data);

glGetError tells me an "GL_INVALID_ENUM"

must be replaced by:

glTexImage2D (GL_TEXTURE_2D, 0, [b]GL_RGB[/b], taillex, tailley, 0, GL_RGB, GL_UNSIGNED_BYTE, data);


I have not had time yet to test gldebugger (but I'll do it soon)

thank you very much Clb for helping me find this bug.

another question:

attriblist int [] = {WGL_CONTEXT_MAJOR_VERSION_ARB, MAJOR, WGL_CONTEXT_MINOR_VERSION_ARB, MINOR, [b]WGL_CONTEXT_PROFILE_MASK_ARB, WGL_CONTEXT_CORE_PROFILE_BIT_ARB, 0, 0[/b]};

and

attriblist int [] = {WGL_CONTEXT_MAJOR_VERSION_ARB, MAJOR, WGL_CONTEXT_MINOR_VERSION_ARB, MINOR, [b]0[/b]};

appears to be identical?

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I hacked sfml a bit to have this functionality, here's how:
http://en.sfml-dev.org/forums/index.php?topic=7903.0

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      glUseProgram(0);
      glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffer);
      glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0,
                                     GL_TEXTURE_CUBE_MAP_POSITIVE_X + face, texture[1], 0);
      glReadPixels(0, 0, kWidth, kHeight, GL_RED_INTEGER, GL_UNSIGNED_INT, outputValues);
       
      Compute shader is very simple, imageLoad content from texture[0], and imageStore content to texture[1]. Does need to sync after dispatchCompute?
    • By Jonathan2006
      My question: is it possible to transform multiple angular velocities so that they can be reinserted as one? My research is below:
      // This works quat quaternion1 = GEQuaternionFromAngleRadians(angleRadiansVector1); quat quaternion2 = GEMultiplyQuaternions(quaternion1, GEQuaternionFromAngleRadians(angleRadiansVector2)); quat quaternion3 = GEMultiplyQuaternions(quaternion2, GEQuaternionFromAngleRadians(angleRadiansVector3)); glMultMatrixf(GEMat4FromQuaternion(quaternion3).array); // The first two work fine but not the third. Why? quat quaternion1 = GEQuaternionFromAngleRadians(angleRadiansVector1); vec3 vector1 = GETransformQuaternionAndVector(quaternion1, angularVelocity1); quat quaternion2 = GEQuaternionFromAngleRadians(angleRadiansVector2); vec3 vector2 = GETransformQuaternionAndVector(quaternion2, angularVelocity2); // This doesn't work //quat quaternion3 = GEQuaternionFromAngleRadians(angleRadiansVector3); //vec3 vector3 = GETransformQuaternionAndVector(quaternion3, angularVelocity3); vec3 angleVelocity = GEAddVectors(vector1, vector2); // Does not work: vec3 angleVelocity = GEAddVectors(vector1, GEAddVectors(vector2, vector3)); static vec3 angleRadiansVector; vec3 angularAcceleration = GESetVector(0.0, 0.0, 0.0); // Sending it through one angular velocity later in my motion engine angleVelocity = GEAddVectors(angleVelocity, GEMultiplyVectorAndScalar(angularAcceleration, timeStep)); angleRadiansVector = GEAddVectors(angleRadiansVector, GEMultiplyVectorAndScalar(angleVelocity, timeStep)); glMultMatrixf(GEMat4FromEulerAngle(angleRadiansVector).array); Also how do I combine multiple angularAcceleration variables? Is there an easier way to transform the angular values?
    • By dpadam450
      I have this code below in both my vertex and fragment shader, however when I request glGetUniformLocation("Lights[0].diffuse") or "Lights[0].attenuation", it returns -1. It will only give me a valid uniform location if I actually use the diffuse/attenuation variables in the VERTEX shader. Because I use position in the vertex shader, it always returns a valid uniform location. I've read that I can share uniforms across both vertex and fragment, but I'm confused what this is even compiling to if this is the case.
       
      #define NUM_LIGHTS 2
      struct Light
      {
          vec3 position;
          vec3 diffuse;
          float attenuation;
      };
      uniform Light Lights[NUM_LIGHTS];
       
       
    • By pr033r
      Hello,
      I have a Bachelor project on topic "Implenet 3D Boid's algorithm in OpenGL". All OpenGL issues works fine for me, all rendering etc. But when I started implement the boid's algorithm it was getting worse and worse. I read article (http://natureofcode.com/book/chapter-6-autonomous-agents/) inspirate from another code (here: https://github.com/jyanar/Boids/tree/master/src) but it still doesn't work like in tutorials and videos. For example the main problem: when I apply Cohesion (one of three main laws of boids) it makes some "cycling knot". Second, when some flock touch to another it scary change the coordination or respawn in origin (x: 0, y:0. z:0). Just some streng things. 
      I followed many tutorials, change a try everything but it isn't so smooth, without lags like in another videos. I really need your help. 
      My code (optimalizing branch): https://github.com/pr033r/BachelorProject/tree/Optimalizing
      Exe file (if you want to look) and models folder (for those who will download the sources):
      http://leteckaposta.cz/367190436
      Thanks for any help...

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