Computer Science Canada getting a ball to bounce inside a rotating cube?? |
| Author: | coolgirl97 [ Thu Jun 06, 2013 8:37 am ] |
| Post subject: | getting a ball to bounce inside a rotating cube?? |
hey... i was given this assignment where i have a box that needs to rotate in all direction when pressing the arrow keys. There needs to be a ball moving inside the box as well... i've got the box to rotate, and tried to get the ball to bounce around... but i think there's something wrong with my coding... because it is not working.. can u please have a look below, and help?? thank you so much!! --------------------------------------------------------------------------------------------------------------------------------------------------------------------------- %getting the cube setscreen ("graphics:1280,1080") %Variable for Colour var box, background : int %Variable for Size var S : real %Perspective Related Variables var theta, phi, psi : real %Location Related Variables var x_cm, y_cm : real %Cube Related Variables var cube_x, cube_y, cube_z, vort_x, vort_y, vort_z, p_x, p_y : array 1 .. 8 of real %--------------------------------------------------------------------------------------------- const DELTA_TIME := 1 const TIME_DELAY := 10 const DELTA_THETA := 0.1 const DELTA_PHI := 0.1 const DELTA_PSI := 0.1 background := 0 box := 7 S := 200 const ZV := 1500 var ch : string (1) x_cm := 640 y_cm := 600 phi := 0 psi := 0 theta := 300 var t : real const L := 75 const w := 20 t := 0 %--------------------------------------------------------------------------------------------- cube_x (1) := +S cube_y (1) := +S cube_z (1) := +S cube_x (2) := -S cube_y (2) := -S cube_z (2) := -S cube_x (3) := -S cube_y (3) := +S cube_z (3) := +S cube_x (4) := +S cube_y (4) := -S cube_z (4) := -S cube_x (5) := -S cube_y (5) := -S cube_z (5) := +S cube_x (6) := +S cube_y (6) := +S cube_z (6) := -S cube_x (7) := +S cube_y (7) := -S cube_z (7) := +S cube_x (8) := -S cube_y (8) := +S cube_z (8) := -S %--------------------------------------------------------------------------------------------- Draw.FillBox (0, 0, maxx, maxy, background) %--------------------------------------------------------------------------------------------- %Rotative Formula loop for i : 1 .. 8 vort_x (i) := (cos (theta) * cos (phi) * cos (psi) - sin (phi) * sin (psi)) * cube_x (i) - (cos (theta) * cos (phi) * sin (psi) + sin (phi) * cos (psi)) * cube_y (i) + sin (theta) * cos (phi) * cube_z (i) vort_y (i) := (cos (theta) * sin (phi) * cos (psi) + cos (phi) * sin (psi)) * cube_x (i) - (cos (theta) * sin (phi) * sin (psi) - cos (phi) * cos (psi)) * cube_y (i) + sin (theta) * sin (phi) * cube_z (i) vort_z (i) := -sin (theta) * cos (psi) * cube_x (i) + sin (theta) * sin (psi) * cube_y (i) + cos (theta) * cube_z (i) end for for i : 1 .. 8 p_x (i) := vort_x (i) / (1 - vort_z (i) / ZV) p_y (i) := vort_y (i) / (1 - vort_z (i) / ZV) end for %--------------------------------------------------------------------------------------------- %Cube Illustration drawline (round (x_cm + p_x (1)), round (y_cm + p_y (1)), round (x_cm + p_x (3)), round (y_cm + p_y (3)), box) drawline (round (x_cm + p_x (1)), round (y_cm + p_y (1)), round (x_cm + p_x (6)), round (y_cm + p_y (6)), box) drawline (round (x_cm + p_x (1)), round (y_cm + p_y (1)), round (x_cm + p_x (7)), round (y_cm + p_y (7)), box) drawline (round (x_cm + p_x (2)), round (y_cm + p_y (2)), round (x_cm + p_x (4)), round (y_cm + p_y (4)), box) drawline (round (x_cm + p_x (2)), round (y_cm + p_y (2)), round (x_cm + p_x (5)), round (y_cm + p_y (5)), box) drawline (round (x_cm + p_x (2)), round (y_cm + p_y (2)), round (x_cm + p_x (8)), round (y_cm + p_y (8)), box) drawline (round (x_cm + p_x (3)), round (y_cm + p_y (3)), round (x_cm + p_x (5)), round (y_cm + p_y (5)), box) drawline (round (x_cm + p_x (3)), round (y_cm + p_y (3)), round (x_cm + p_x (8)), round (y_cm + p_y (8)), box) drawline (round (x_cm + p_x (4)), round (y_cm + p_y (4)), round (x_cm + p_x (6)), round (y_cm + p_y (6)), box) drawline (round (x_cm + p_x (4)), round (y_cm + p_y (4)), round (x_cm + p_x (7)), round (y_cm + p_y (7)), box) drawline (round (x_cm + p_x (5)), round (y_cm + p_y (5)), round (x_cm + p_x (7)), round (y_cm + p_y (7)), box) drawline (round (x_cm + p_x (6)), round (y_cm + p_y (6)), round (x_cm + p_x (8)), round (y_cm + p_y (8)), box) delay (TIME_DELAY) drawline (round (x_cm + p_x (1)), round (y_cm + p_y (1)), round (x_cm + p_x (3)), round (y_cm + p_y (3)), white) drawline (round (x_cm + p_x (1)), round (y_cm + p_y (1)), round (x_cm + p_x (6)), round (y_cm + p_y (6)), white) drawline (round (x_cm + p_x (1)), round (y_cm + p_y (1)), round (x_cm + p_x (7)), round (y_cm + p_y (7)), white) drawline (round (x_cm + p_x (2)), round (y_cm + p_y (2)), round (x_cm + p_x (4)), round (y_cm + p_y (4)), white) drawline (round (x_cm + p_x (2)), round (y_cm + p_y (2)), round (x_cm + p_x (5)), round (y_cm + p_y (5)), white) drawline (round (x_cm + p_x (2)), round (y_cm + p_y (2)), round (x_cm + p_x (8)), round (y_cm + p_y (8)), white) drawline (round (x_cm + p_x (3)), round (y_cm + p_y (3)), round (x_cm + p_x (5)), round (y_cm + p_y (5)), white) drawline (round (x_cm + p_x (3)), round (y_cm + p_y (3)), round (x_cm + p_x (8)), round (y_cm + p_y (8)), white) drawline (round (x_cm + p_x (4)), round (y_cm + p_y (4)), round (x_cm + p_x (6)), round (y_cm + p_y (6)), white) drawline (round (x_cm + p_x (4)), round (y_cm + p_y (4)), round (x_cm + p_x (7)), round (y_cm + p_y (7)), white) drawline (round (x_cm + p_x (5)), round (y_cm + p_y (5)), round (x_cm + p_x (7)), round (y_cm + p_y (7)), white) drawline (round (x_cm + p_x (6)), round (y_cm + p_y (6)), round (x_cm + p_x (8)), round (y_cm + p_y (8)), white) %--------------------------------------------------------------------------------------------- % Manipulating the Cube if hasch then getch (ch) %Turn Upwards if ch = chr (200) then psi := psi + DELTA_PSI %Turn Downwards elsif ch = chr (208) then psi := psi - DELTA_PSI %Turn Right elsif ch = chr (205) then theta := theta + DELTA_THETA %Turn Left elsif ch = chr (203) then theta := theta - DELTA_THETA end if end if % ______________________________________________________________________________________________________________________ const DELTATIME := 0.10 const TIMEDELAY := 10 var x, y, z, x0, y0, z0, v0x, v0y, v0z, T : real const x_right_boundary := 1100 const x_left_boundary := 250 const y_top_boundary := 1000 const y_bottom_boundary := 250 const RADIUS := 0.025 const DEPTH_SCALE := 0.1 x0 := 100 y0 := 100 z0 := 100 v0x := 30 v0y := 10 v0z := 20 T := 0 x := x0 + v0x * T y := y0 + v0y * T z := z0 + v0z * T drawoval (645, 600, 20, 20, black) delay (TIME_DELAY) drawfilloval (645, 600, 20, 20, white) T := T + 1 if x > x_right_boundary then x0 := 2 * x_right_boundary - x y0 := y v0x := -v0x T := 0 end if if x < x_left_boundary then x0 := 2 * x_left_boundary - x v0x := -v0x y0 := y T := 0 end if if y > y_top_boundary then y0 := 2 * y_top_boundary - y v0y := -v0y x0 := x T := 0 end if if y < y_bottom_boundary then y0 := 2 * y_bottom_boundary - y v0y := -v0y x0 := x T := 0 end if end loop |
|
| Author: | MihaiG [ Thu Jun 06, 2013 8:04 pm ] | ||
| Post subject: | Re: getting a ball to bounce inside a rotating cube?? | ||
Cool program, before we go ahead and address the main issue you're having lets talk about some basic code practices. In your main loop you have (roughly lines 170) a bunch of variable/constant declaration inside a loop.. does this seem right? We can move those outside the loop. I usually keep all my parameters at the very top so i can easily adjust them! Second of all, try to refrain from using getch, it only allows for the detection of one key intut at a time, i like using Input.KeyDown In the code below
You seem to be forgetting what happens if it hits the z boundry! Your drawing code can be placed in a seperate procedure so your code can be more readable. From a quick look. I think you need to read up on planes in R3 (3d space). Your if statements try to assume that even if we rotate the cube each side has a fixed value for x,y,z while in reality, they have a wide range of values. Ie. If the ball hits the bottom of the cube near the front the x could be 5 while if it hits it at the back it could be -10. This is a tough endeavor, your concept for rotating in 3d is well done. I might suggest trying to bounce the ball of a square rotating in R2 space. Once you understand the concept youll see it's not a matter of if x < a certain value. It's if a point interesects with a plane in R3. If you can show me an example of a rotating square in 2d and a ball bouncing around i will guide and give you some further tips! |
|||
| Author: | scii [ Tue Aug 13, 2013 12:42 am ] |
| Post subject: | Re: getting a ball to bounce inside a rotating cube?? |
You can search it in google |
|