The UI coordinate system
Factor handbook » UI framework » Implementing new gadgets » Customizing gadget appearance » Implementing custom drawing logic
Factor handbook » UI framework » Implementing new gadgets » Customizing gadget appearance » Implementing custom drawing logic
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The UI uses a coordinate system where the y axis is oriented down. The OpenGL GL_MODELVIEW matrix is saved or restored when rendering a gadget, and the origin is translated to the gadget's origin within the window. The current origin is stored in a variable:
Gadgets must not draw outside of their bounding box, however clipping is not enforced by default, for performance reasons. This can be changed by setting the clipped? slot to t in the gadget's constructor.
origin
Gadgets must not draw outside of their bounding box, however clipping is not enforced by default, for performance reasons. This can be changed by setting the clipped? slot to t in the gadget's constructor.