resizing QGLWidget to fit with each sprite size I have

Question

I'm creating 2D Map editor using opengl to draw simple 32x32 sprites but it seems that I cannot resize my QGLWidget to a large size (i.e size * sprite size -> 1024 * 32), using 1024 only seems to work fine (using glwidget->setMinimumSize(...)). I've been googling for a while now about this, the only interesting thing I found is subclassing QAbstractScrollArea and setting my QGLWidget as it's viewport (That's what QGraphicsView does), I also seen all Qt opengl examples but i couldn't find anything that could help (except Image Viewer example which is not exactly what I want), I also tried the following: horizontalScrollBar()->setMaximum(width * 32); verticalScrollBar()->setMaximum(height * 32); with the widget resizable set to true/false on the scrollarea but still nothing. Any ideas how would I do that? I can show more code if you ask me to.

Using Qt v4.7.3.

Answer 1

I have two ideas:

If it's possible, drop the idea of using a QGLWidget and place the sprites directly in a graphics scene (QGraphicsPixmapItem). Possibly not what you want, but the graphics scene is made to handle a lot of items, so most things you need (trigger mouse events on items for example) are already implemented.

Or just place the QGLWidget in a graphics scene using a QGraphicsWidget. This should automatically tell the scene its size, which then tells the view the size of the scene. The scroll bars appear automatically if the scene doesn't fit into the view.

Update:

As described in this link, you can use OpenGL in any graphics view:

view.setViewport(new QGLWidget(QGLFormat(QGL::SampleBuffers)));
view.setViewportUpdateMode(QGraphicsView::FullViewportUpdate);