Tiling with OpenGL and textures

[soxs060389]

I try to make a wall of pictures (no overlapping).
For this case I made simple proof of concept example code, but I encounterd one major drawback:
This solution renders ONLY the last texture and replaces all previuosly loaded ons with that one.
(Code compiles just fine)

#include <QtCore>
#include <QImage>
#include <QApplication>
#include <QtOpenGL>
#include <QtDebug>
 
class Tile {
public:
    Tile(GLfloat x, GLfloat y, QString path) : gl_x(x), gl_y(y) {
        QImage t;
        QImage b;
        b.load(path);
        t = QGLWidget::convertToGLFormat( b );
        glGenTextures( 1, &texid );
        qDebug() << "texid tile = " << texid;
        glBindTexture( GL_TEXTURE_2D, texid );
        glTexImage2D( GL_TEXTURE_2D, 0, 3, t.width(), t.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, t.bits() );
        glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
        glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
    }
    virtual ~Tile(){
        glDeleteTextures(1,&texid);
    }
    void draw(){
        glPushMatrix();
        glTranslatef(64.0f * gl_x, 64.0f * gl_y, 0.0f); // just to avoid total overlapping
        glBindTexture(1,texid);
        qDebug() << "draw texid" << texid;
        glBegin(GL_QUADS);
            glTexCoord2f(1.0f,1.0f);
            glVertex2f(0.0f,0.0f);
 
            glTexCoord2f(1.0f,0.0f);
            glVertex2f(0.0f,128.0f);
 
            glTexCoord2f(0.0f,0.0f);
            glVertex2f(128.0f,128.0f);
 
            glTexCoord2f(0.0f,1.0f);
            glVertex2f(128.0f,0.0f);
        glEnd();
        glPopMatrix();
    }
private:
    GLfloat gl_x;
    GLfloat gl_y;
    GLuint texid;
 
};
 
 
// THE GL WIDGET CLASS
class GLTest : public QGLWidget
{
public:
    GLTest(QWidget* parent = 0);
    virtual ~GLTest();
protected:
    void initializeGL();
    void resizeGL(int w, int h);
    void paintGL();
 
    QList<Tile*> tiles;
};
 
GLTest::GLTest(QWidget* parent) : QGLWidget(parent)
{
 
}
GLTest::~GLTest()
{
    for (QList<Tile*>::iterator i = tiles.begin(); i!=tiles.end(); ++i)
    {
        delete (*i);
    }
}
 
void GLTest::initializeGL()
{
    glClearColor(0.5f,0.5f,0.5f,1.0f);
    glEnable(GL_TEXTURE_2D);
    qDebug() << "init GL ";
    tiles.append(new Tile(0.0f, 2.0f, QString("./images/side1.png")));
    tiles.append(new Tile(1.0f, 3.0f, QString("./images/side2.png")));
    tiles.append(new Tile(3.0f, 4.0f, QString("./images/side4.png")));
 
}
 
void GLTest::resizeGL(int w, int h)
{
 
    glMatrixMode (GL_PROJECTION);
    glLoadIdentity ();
    glOrtho(0, w, h, 0, -1, 1);
    glMatrixMode(GL_MODELVIEW);
    glViewport(0,0,w, h);
    glLoadIdentity();
}
 
void GLTest::paintGL()
{
 
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    glColor3f(1.0f,1.0f,1.0f);
 
    for (QList<Tile*>::iterator i = tiles.begin(); i!=tiles.end(); ++i)
    {
        (*i)->draw();
    }
 
}
 
int main(int argc, char** argv)
{
    QApplication app(argc, argv);
    GLTest gltest;
    gltest.show();
    return app.exec();
}

#include <QtCore>
#include <QImage>
#include <QApplication>
#include <QtOpenGL>
#include <QtDebug>

class Tile {
public:
    Tile(GLfloat x, GLfloat y, QString path) : gl_x(x), gl_y(y) {
        QImage t;
        QImage b;
        b.load(path);
        t = QGLWidget::convertToGLFormat( b );
        glGenTextures( 1, &texid );
        qDebug() << "texid tile = " << texid;
        glBindTexture( GL_TEXTURE_2D, texid );
        glTexImage2D( GL_TEXTURE_2D, 0, 3, t.width(), t.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, t.bits() );
        glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR );
        glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );
    }
    virtual ~Tile(){
        glDeleteTextures(1,&texid);
    }
    void draw(){
        glPushMatrix();
        glTranslatef(64.0f * gl_x, 64.0f * gl_y, 0.0f); // just to avoid total overlapping
        glBindTexture(1,texid);
        qDebug() << "draw texid" << texid;
        glBegin(GL_QUADS);
            glTexCoord2f(1.0f,1.0f);
            glVertex2f(0.0f,0.0f);

            glTexCoord2f(1.0f,0.0f);
            glVertex2f(0.0f,128.0f);

            glTexCoord2f(0.0f,0.0f);
            glVertex2f(128.0f,128.0f);

            glTexCoord2f(0.0f,1.0f);
            glVertex2f(128.0f,0.0f);
        glEnd();
        glPopMatrix();
    }
private:
    GLfloat gl_x;
    GLfloat gl_y;
    GLuint texid;

};


// THE GL WIDGET CLASS
class GLTest : public QGLWidget
{
public:
    GLTest(QWidget* parent = 0);
    virtual ~GLTest();
protected:
    void initializeGL();
    void resizeGL(int w, int h);
    void paintGL();

    QList<Tile*> tiles;
};

GLTest::GLTest(QWidget* parent) : QGLWidget(parent)
{

}
GLTest::~GLTest()
{
    for (QList<Tile*>::iterator i = tiles.begin(); i!=tiles.end(); ++i)
    {
        delete (*i);
    }
}

void GLTest::initializeGL()
{
    glClearColor(0.5f,0.5f,0.5f,1.0f);
    glEnable(GL_TEXTURE_2D);
    qDebug() << "init GL ";
    tiles.append(new Tile(0.0f, 2.0f, QString("./images/side1.png")));
    tiles.append(new Tile(1.0f, 3.0f, QString("./images/side2.png")));
    tiles.append(new Tile(3.0f, 4.0f, QString("./images/side4.png")));

}

void GLTest::resizeGL(int w, int h)
{

    glMatrixMode (GL_PROJECTION);
    glLoadIdentity ();
    glOrtho(0, w, h, 0, -1, 1);
    glMatrixMode(GL_MODELVIEW);
    glViewport(0,0,w, h);
    glLoadIdentity();
}

void GLTest::paintGL()
{

    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    glColor3f(1.0f,1.0f,1.0f);

    for (QList<Tile*>::iterator i = tiles.begin(); i!=tiles.end(); ++i)
    {
        (*i)->draw();
    }

}

int main(int argc, char** argv)
{
    QApplication app(argc, argv);
    GLTest gltest;
    gltest.show();
    return app.exec();
}

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Thx for any help and suggestions.

[soxs060389]

Replace line 27 with

glBindTexture(GL_TEXTURE_"D,texid);

glBindTexture(GL_TEXTURE_"D,texid);

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and it works.. this nasty thingy made me hicup 2 days -.-