How to check if object is in viewport Directx 11

Solution 1:

For a perspective projection, this is a 'frustum' vs. 'box' bounding-volume intersection test.

For a orthographic projection, this is a 'box' vs. 'box' bounding-volume intersection test.

The DirectXMath library (it's also in the Windows SDK) includes functions to perform these tests in the DirectXCollision.h header. Create a BoundingFrustum object instance using your projection matrix from your camera:

BoundingFrustum fr(proj);
// use fr(proj, true) if using right-handed instead of left-handed view setup

Create a BoundingBox or BoundingOrientedBox for your object's location:

BoundingBox box(position, extents);

Then use fr.Contains(box) to see if it returns DISJOINT.

References for these kinds of computations include:

• Akenine-Möller, Haines, and Hoffman, "Real-Time Rendering", AK Peters/CRC Press (2018)

• Ericson, "Real-Time Collision Detection", Morgan Kaufmann (2005)

• Glassner, "An Introduction to Ray Tracing", Morgan Kaufmann (1989)

• Schneider and Eberly, "Geometric Tools for Computer Graphics", Morgan Kaufmann (2003)