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+--- Thread: 2D sprite to bounding box hit test (/showthread.php?tid=4446)
2D sprite to bounding box hit test - BiMMate - 04-17-2024
Is there a way to get elements inside a 2D rectangle?
I mean, probably I can draw an overly sprite for the rectangle following user's pointer, but after having screen U,V coordinates I'll need a hit test on elements that I don't know how to solve. Maybe getting a camera direction ray and move it along the edges, but that would not retrieve elements inside the rectangle.
Maybe a bounding box created from perpendicular plane to camera and long enough could do the job, but I am totally lost
Any tip about this?
RE: 2D sprite to bounding box hit test - abenedik - 04-23-2024
I have just added a new sample that shows how to render scene to ID bitmap where each object is rendered with its own color that represents the ID of the object (https://github.com/ab4d/Ab4d.SharpEngine.Samples/blob/main/Ab4d.SharpEngine.Samples.Common/HitTesting/HitTestingWithIdBitmapSample.cs).
This sample shows how to get the hit object by checking the colors at the specified mouse coordinates.
Get the latest version of the samples to get the new "Hit-testing with ID bitmap".
This sample can be easily extended to get objects in a rectangle by checking the colors in the rectangular area instead of checking the color of a single pixel.