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How to adjust for window being resized in OpenGL?
In case of legacy (fixed function pipeline) OpenGL, you can do it the following ways: If you’re using something like gluPerspective () just use the window width/height ratio:
Do you turn back face culling off in OpenGL?
Here’s the result. Make sure to turn backface culling off (glDisable (GL_CULL_FACE) ) because since we can look through the mesh, we could see that it has no “back” face. Order matters !
Do you have to switch texture for transparent triangles?
Sorting all the transparent triangles takes time If you have to switch your texture, or worse, your shader, from triangle to triangle, you’re going into deep performance trouble. Don’t do this. A good enough solution is often to : If they are supposed to look very different, use your texture !
What’s the best way to do transparency in a shader?
A number of other techniques are worth investigating if your engine really, really needs state-of-the-art transparency : The original 2001 Depth Peeling paper: pixel-perfect results, not very fast. Several papers on bucket sort. Uses an array of fragments; sort them by depth in a shader.
When to call glviewport in Java OpenGL?
Finally, whenever the window is re-sized, make a call to glViewport with the updated screen resolution. This will scale your figures. Is this the correct way to ensure that models take the same proportion of screen-space on different resolutions? Should I be using a projection equal to the resolution as well?
How can I adjust for the window being resized?
I am drawing several shapes (such as circles) that are keyed off of the window height & width. Since the window always starts at a given size, they are drawn correctly, but when the window is resized, it messes the aspect ratio up. How can I draw the shapes properly, regardless of window size?
How to fix field of view in OpenGL?
In a perspective-projection 3D game with no HUD, the usual simple solution (available in OpenGL as part of gluPerspective) is to fix the projection’s field of view relative to the vertical dimension.
How to draw relative to screen size in OpenGL?
You would have to init window size and set Ortho to the size of the screen (current display resolution), then draw relative to the size of the window. This is basic template that I use…
Which is the glortho call in OpenGL?
OpenGL uses a viweing frustum which in normalized device space is a cube in the range [-1,1] along all 3 dimensions. The glOrtho() call is typically used to set up a projection matrix, which will transform eye space coordinates into clip space.