tri¶

draw one 3D triangle from the shell
NAME
    tri - draw one 3D triangle from the shell

SYNOPSIS
    tri x0 y0 z0 x1 y1 z1 x2 y2 z2 [f] [k] [r g b]

DESCRIPTION
    Draws a triangle given three world-space corners (16-bit numbers;
    x right, y UP, z into the screen, camera at the origin; keep z at
    16 or more or the near plane clips it away). Flags after the nine
    coordinates: `f` fills the triangle, `k` KEEPS the scene (appends
    this triangle to GL command list 0 instead of starting it fresh, so
    several tri commands stack -- and rotate/camera replay the whole
    ensemble from any angle; stage 10c). An optional
    colour follows as r g b (r and b 0-31, g 0-63); white if omitted.

    The frame is the house default: window -120..120 on the view plane,
    the centred square viewport, focal length 256 -- so a point at
    z=256 maps roughly 1:1, nearer looms, farther shrinks. Rendering
    uses the GL engine when fitted (the fabric clips, projects
    and scan-fills it) and the software pipeline otherwise -- the same
    pixels either way. No page flip: POINT reads back what was drawn.

EXAMPLES
    tri -80 -80 300 80 -80 300 0 40 420 f 31 0 0
        the stage-9 proof triangle, filled red

    tri -100 -100 250 100 -100 250 0 100 250 f 0 63 0
        a flat green filled triangle facing you at depth 250

    tri -100 -100 250 100 -100 250 0 100 250 k
        ...its white outline stacked on top (k = keep)

    tri -110 0 100 110 0 900 0 90 400 f 0 0 31
        a blue sliver leaning far into the distance

SEE ALSO
    g3d (the library this fronts), cube, basic