| 0,0 → 1,68 |
|---|
| --PICTURE scene: Ellipse update-demo (anim) |
| --Demonstrates 'interactive' features. |
| --by Richard Fhager |
| |
| -- Copyright 2011 Richard Fhager |
| -- |
| -- This program is free software; you can redistribute it and/or |
| -- modify it under the terms of the GNU General Public License |
| -- as published by the Free Software Foundation; version 2 |
| -- of the License. See <http://www.gnu.org/licenses/> |
| |
| |
| -- |
| -- rot: Rotation in degrees |
| -- stp: Step is # of line segments (more is "better") |
| -- a & b are axis-radius |
| function ellipse2(x,y,a,b,stp,rot,col) |
| local n,m=math,rad,al,sa,ca,sb,cb,ox,oy,x1,y1,ast |
| m = math; rad = m.pi/180; ast = rad * 360/stp; |
| sb = m.sin(-rot * rad); cb = m.cos(-rot * rad) |
| for n = 0, stp, 1 do |
| ox = x1; oy = y1; |
| sa = m.sin(ast*n) * b; ca = m.cos(ast*n) * a |
| x1 = x + ca * cb - sa * sb |
| y1 = y + ca * sb + sa * cb |
| if (n > 0) then drawline(ox,oy,x1,y1,col); end |
| end |
| end |
| -- |
| |
| setpicturesize(300,300) |
| setcolor(0,96,96,96) |
| setcolor(1,255,255,128) |
| |
| r1 = 100 |
| r2 = 50 |
| rt = 0 |
| |
| frames = 100 |
| |
| |
| while (1 < 2) do |
| |
| r1t = 10 + math.random() * 140 |
| r2t = 10 + math.random() * 140 |
| rtt = math.random() * 360 |
| |
| for n = 0, frames-1, 1 do |
| clearpicture(0) |
| |
| f2 = n / frames |
| f1 = 1 - f2 |
| |
| r1a = r1*f1 + r1t*f2 |
| r2a = r2*f1 + r2t*f2 |
| rta = rt*f1 + rtt*f2 |
| |
| -- x, y, r1, r2, stp, rot, col |
| ellipse2(150, 150, r1a, r2a, 50, rta, 1) |
| |
| statusmessage('press ESC to stop') |
| updatescreen();if (waitbreak(0)==1) then return end |
| |
| end |
| |
| r1,r2,rt = r1a,r2a,rta |
| |
| end |