I want to render only what is viewed in the view, the first thing I need is to obtain the left top pixel of the current visualization, in order to get first tile that I want to draw. How can I obtain this pixel? I have been looking the View wiki and didn't found anything.
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I'm looking the tutorials and I see that you can define the Viewport, setting a FloatRect with left, top, witdh and height parameters.
So I have to get the viewport from the current view and get the x and y attributes. This would work if viewport is defined with pixels, not with relative position to the window.
I'm lost at this point.