pmat
pmat "m0 m1 m2 ... m15"PMAT(nged)
NAME
pmat - get or set the perspective projection matrix
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SYNOPSIS
DESCRIPTION
The pmat command gets or sets the perspective projection matrix for the current view.
-
No arguments: Returns the current projection matrix as a 16-element space-separated floating-point string representing the 4×4 matrix in row-major order. This matrix controls perspective rendering.
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One argument: Sets the projection matrix from a provided 16-element space-separated string. The string must contain exactly 16 floating-point values. The view is updated immediately after the change.
The perspective matrix is normally managed automatically by the perspective command, which sets it from a field-of-view angle. Use pmat to inspect the current matrix or to provide a custom projection matrix directly.
When perspective is disabled (perspective 0), the projection matrix is the identity and pmat returns: 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1.
EXAMPLES
Example 1. Retrieve the current perspective matrix
mged> pmat
Returns the current perspective projection matrix as 16 numbers. When perspective is active (e.g. after perspective 45), this will be a non-identity matrix; when orthographic, it will be the identity.
Example 2. Inspect the matrix after setting perspective
mged> perspective 60 mged> pmat
Sets the perspective angle to 60° and then retrieves the resulting projection matrix to examine the constructed values.
Example 3. Set the perspective matrix explicitly
mged> pmat "1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1"
Sets the projection matrix to the identity, equivalent to perspective 0. The quoted string must contain exactly 16 space-separated values.
AUTHOR
BRL-CAD Team
BUG REPORTS
Reports of bugs or problems should be submitted via electronic mail to devs@brlcad.org