Code archives/3D Graphics - Maths/simple ball physics
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| Types and simple ball physics |
; this is an experiment in physics and types ; Bill Radford 2001 ; from the outset I am attempting to attach physical properties to 3d objects ; using Blitz's TYPE command set. I am new to this (about 1 week) so if you find a better ; method of doing this or improve my code, please let me know b_radford@yahoo.com ; ; please comment ; set up the display ; graphics If Windowed3D () ; see if the Graphics card supports 3D in a window, if not go to fullscreen Graphics3D 640, 480, 0, 2 Else Graphics3D 640, 480, 0, 1 EndIf SetBuffer BackBuffer () ; point all drawing to the hidden back buffer which we will eventually FLIP light=CreateLight() cam=CreateCamera() MoveEntity cam,20,10,-20 ; VARIABLE LIST Gravity# = .01 Friction# = .99 ; End OF VARIABLE LIST Gosub create_objects Gosub define_types y#=20 Repeat For thing.ball = Each ball ; cycle through all the "balls" and set the position thing\posy#=thing\posy#+thing\yvel# ; yposition = yposition + Velocity thing\yvel#=thing\yvel#-gravity# ; velocity = velocity - gravity ; if the ball hits the ground, convert the velocity value to a positive number with the ABS() function ; and multiply it by the balls elasticity value to dissipate some of the energy. .1=flab 1.1=flubber If thing\posy#<1 Then thing\yvel#=Abs(thing\yvel#) * thing\elasticity# PositionEntity thing\entity,thing\posx#,thing\posy#,thing\posz# Next RenderWorld UpdateWorld Text 0,0, y# Flip Until KeyHit(1)=1 ; keep looping (repeating) until the Escape key is hit ; ************************************************* .create_objects ; label for the gosub command to find this subroutine ballmodel=CreateSphere(6) ;HideEntity ballmodel PositionEntity ballmodel,0,50,0 plane=CreatePlane() ; CreatePlane ( [sub_divs][,parent] ) EntityColor plane,240,5,5 Return ; ; ************************************************** .define_types Type ball Field posx#,posy#,posz# Field entity Field mass,weight,size Field xvel#,yvel#,zvel# Field elasticity#,alpha# End Type For x=1 To 8 ; number of balls (8x8=64) For z=1 To 8 thing.ball = New ball thing\entity = CopyEntity(ballmodel) thing\posx# = x*4 ; set the x position thing\posy# = 30 ; thing\posz# = z*4 ; set the z positon thing\elasticity#=Rnd(.7,.89) EntityColor thing\entity,Rnd(1,255),Rnd(1,255),Rnd(1,255) PositionEntity thing\entity,thing\posx#,thing\posy#,thing\posz# thing\alpha# = .6 EntityAlpha thing\entity,thing\alpha# Next Next Return |