Function perspective_LH_M11

Build a perspective projection matrix with left-hand NDC and [-1 .. 1] depth clipping


						
				Mat4!T perspective_LH_M11(T)
				(
				

				  in T fovx,
				

				  in T aspect,
				

				  in T near,
				

				  in T far
				

				)
				

				if (isFloatingPoint!T);

Parameters

Name	Description
fovx	horizontal field of view in degrees
aspect	aspect ratio (width / height)
near	position of the near plane
far	position of the far plane

Returns

a matrix that maps from eye space to clip space. To obtain NDC, the vector must be divided by w.

Example

const m = perspective_LH_M11!float(90, 2, 2, 4);
const vl = fvec(-2, -1, -2);
const vh = fvec(4, 2, -4);
const vc = fvec(0, 0, -3);

auto toNdc(in FVec3 v) {
    const clip = m * fvec(v, 1);
    return (clip / clip.w).xyz;
}

import gfx.math.approx : approxUlp;
assert(approxUlp( toNdc(vl), fvec(-1, -1, -1) ));
assert(approxUlp( toNdc(vh), fvec(1, 1, 1) ));
assert(approxUlp( toNdc(vc), fvec(0, 0, 1f/3f) ));