How to write 3D applications?

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And now we put all that together and get this:

my3dwidget.h

#ifndef MY3DWIDGET_H
#define MY3DWIDGET_H

#include <QOpenGLWidget>
#include <QOpenGLFunctions>
#include <array>
#include <QOpenGLShaderProgram>
#include <QOpenGLBuffer>
#include <QOpenGLVertexArrayObject>

class My3dWidget
        : public QOpenGLWidget
        , protected QOpenGLFunctions
{
    Q_OBJECT
public:
    explicit My3dWidget(QWidget *parent = nullptr);

protected:
    virtual void initializeGL() override;
    virtual void resizeGL(int w, int h) override;
    virtual void paintGL() override;

private:
    std::array<float, 3 * 2> m_vertices = {{ // 3 vertices * 2 coordinates
        -0.75f, -0.75f, // vertex 1 : x, y
        -0.75f,  0.75f, // vertex 2 : x, y
         0.75f,  0.75f  // vertex 3 : x, y
    }};

    QOpenGLShaderProgram m_program;
    QOpenGLBuffer m_buffer;
    QOpenGLVertexArrayObject m_vao;
};

#endif // MY3DWIDGET_H

my3dwidget.cpp

#include "my3dwidget.h"

My3dWidget::My3dWidget(QWidget *parent)
    : QOpenGLWidget(parent)
{
}

void My3dWidget::initializeGL()
{
    initializeOpenGLFunctions();
    glClearColor(0.0f, 0.0f, 1.0f, 1.0f); // blue

    m_program.addShaderFromSourceFile(QOpenGLShader::Vertex, ":/shaders/shader.vert");
    m_program.addShaderFromSourceFile(QOpenGLShader::Fragment, ":/shaders/shader.frag");
    m_program.link();
    m_program.bind();

    m_buffer.create();
    m_buffer.bind();
    m_buffer.allocate(m_vertices.data(), // pointer to first element of array
                      sizeof(m_vertices)); // size of array in bytes

    m_vao.create();
    m_vao.bind();
    m_program.enableAttributeArray(0); // vertex array at location 0
    m_program.setAttributeBuffer(0, // location 0
                                 GL_FLOAT, // elements of the array are of type GL_FLOAT (= float)
                                 0, // start at array position 0
                                 2, // number of elements per vertex (= x, y)
                                 0); // stride: densely packed (= no holes)

    m_vao.release();
    m_buffer.release();
    m_program.release();
}

void My3dWidget::resizeGL(int w, int h)
{
    Q_UNUSED(w)
    Q_UNUSED(h)
}

void My3dWidget::paintGL()
{
    glClear(GL_COLOR_BUFFER_BIT);
    m_program.bind();
    m_vao.bind();
    glDrawArrays(GL_TRIANGLES, 0, sizeof(m_vertices));
    m_vao.release();
    m_program.release();
}

End of tutorial.

parvizwpf

very very thanks friend.
so why i could not run qt 5 tutorial? link text
what about GLUT? can i use glut commands in Qt?
can i ask my questions if i had more on future?
UPDATED:
i can to run trent reed tutorial finally. of course in my laptop. but on my work pc not run. that get erros: ~~link text~~

[Edit: removed link, contains malware ~~ @Wieland]

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@parvizwpf said in How to write 3D applications?:

very very thanks friend

No worries. Please mark the thread as solved and vote-up the posts that were helpful.

can i ask my questions if i had more on future

Sure. Please start a new thread for each specific question.

i can to run it of course in my laptop. but on my work pc not run. that get erros: link text

The domain you linked to contains malware. Please use a different image hoster, e.g. http://postimages.org/

parvizwpf

repaired error image link
what about GLUT? can i use glut commands in Qt?
whatever you help me to start opengl :-)))
"vote-up the posts that were helpful." how?

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GLUT is old and stinks. You don't want to touch it.

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@parvizwpf said in How to write 3D applications?:

"vote-up the posts that were helpful." how?

see https://forum.qt.io/topic/71830

parvizwpf

why? i see it in many web tutorials.

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@parvizwpf said in How to write 3D applications?:

why? i see it in many web tutorials

because all these tutorials are outdated and written by n00bs

parvizwpf

i can not see anything in your topic link.
how can i create a quote? i don't see it.
n00bs???? if those are n00bs ,so who am i?
do you tell me good tutorials ?

? Offline

Edit: Oops, looks like you've been faster :-)

parvizwpf

[????????]

? Offline

but on my work pc not run.

Maybe your PC has a terribly outdated GPU or the driver has some problem.

do you tell me good tutorials ?

Actually I like Trent's tutorial for the Qt integration part. Anything else: get a book on GLSL.

parvizwpf

@Wieland
maybe. you right.
Good luck.