Drawing a box, kinda - GameCreators Forum

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Melancholic

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Posted: 9th Aug 2010 09:39

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So here is my problem, I thought this would be pretty simple but I seem to have been proved wrong. I need to draw a box on screen in 3d, though I am not sure how this is done, I have tried a few methods but none have worked, below is some code of mine

+ Code Snippet

pick screen MOUSEX(),MOUSEY(),0
NONEED = pick object(MOUSEX(),MOUSEY(),0,1000)
MOSX = Get Pick Vector X()
MOSY = Get Pick Vector y()
text 50,50,STR$(MOSX)
text 50,100,STR$(MOSY)

loop

//Create box function
Function drawbox()

//get mouse position variables
XORIG=MOUSEX()
YORIG=MOUSEY()

//loop for box drawing proccess
while Mouseclick()=1
sync

//get screen coordinates
pick screen MOUSEX(),MOUSEY(),0
NONEED = pick object(MOUSEX(),MOUSEY(),0,1000)
MOSX2 = Get Pick Vector X()
MOSY2 = Get Pick Vector y()
text 50,50,STR$(MOSX)
text 50,100,STR$(MOSY)

//make variables to draw box


//draw the region box


endwhile

endfunction

As you can see I am storing the 3d position of the mouse just as the mouse was clicked(in the mosx and mosy variables). Then as the mouse is being held down I am recording its position in mosx2 and mosy2, plus I have 2d screen coordinates just for good measure.

This is for a 2.5d project so the z axis doesn’t matter, all object are positioned at o on the z axis. I am very thankful for any help

I can count to banana...

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baxslash

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Posted: 9th Aug 2010 11:52 Edited at: 9th Aug 2010 11:55

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Quote: "MOSX2 = Get Pick Vector X()
MOSY2 = Get Pick Vector y()"

This will only get the vectors from the camera position. Also you are only getting an X and Y (3D needs Z too). To get the world 3D coordinates you need to have this:

+ Code Snippet

MOSX2 = Get Pick Vector X()+camera position x()
MOSY2 = Get Pick Vector y()+camera position y()
MOSZ2 = Get Pick Vector z()+camera position z()

...then you could use the points you are storing and the points from the 'current' position of the mouse to scale and position a plain...

+ Code Snippet

`work out the centre of the selected area
CX#=MOSX+(MOSX2-MOSX)*.5
CY#=MOSY+(MOSY2-MOSY)*.5
CZ#=MOSZ+(MOSZ2-MOSZ)*.5

`work out the scale
SX#=abs(MOSX2-MOSX)
SZ#=abs(MOSZ2-MOSZ)

`add the plain object maybe do this every 10th of a second to avoid lag
p=99 `or any free object number
if object exist(p) then delete object p
make object plain p,SX#,SZ#
position object p,CX#,CY#,CZ#
point object p,CX#,CY#+1,CZ#
`add textures etc for the plain here

Hope that works or at least helps!

EDIT: Just added the rotation correction for the plain!

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Melancholic

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Posted: 9th Aug 2010 13:57

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Thanks, that seemed to work somewhat. But i get a sort of sharp edge on the created plane. My code is

do
sync
xeno update
pick screen MOUSEX(),MOUSEY(),0
NONEED = pick object(MOUSEX(),MOUSEY(),0,1000)
MOSX = Get Pick Vector X()+camera position x()
MOSY = Get Pick Vector y()+camera position y()
MOSZ = Get Pick Vector z()+camera position z()
text 50,50,STR$(MOSX)
text 50,100,STR$(MOSY)

drawbox()

loop

//Create box function
Function drawbox()

//get mouse position variables
XORIG=MOUSEX()
YORIG=MOUSEY()

//get screen coordiantes
while Mouseclick()=1
sync

//get screen coordinates
pick screen MOUSEX(),MOUSEY(),0
NONEED = pick object(MOUSEX(),MOUSEY(),0,1000)
MOSX2 = Get Pick Vector X()+camera position x()
MOSY2 = Get Pick Vector y()+camera position y()
MOSZ2 = Get Pick Vector z()+camera position z()
text 50,50,STR$(MOSX)
text 50,100,STR$(MOSY)
text 50,150,STR$(SX#)

`work out the centre of the selected area
CX#=MOSX+(MOSX2-MOSX)*.5
CY#=MOSY+(MOSY2-MOSY)*.5
CZ#=MOSZ+(MOSZ2-MOSZ)*.5

`work out the scale
SX#=abs(MOSX2-MOSX)
SZ#=abs(MOSZ2-MOSZ)

`add the plain object maybe do this every 10th of a second to avoid lag
p=99 `or any free object number
if object exist(p) then delete object p
make object plain p,SX#,SZ#
position object p,CX#,CY#,CZ#
point object p,CX#,CY#+1,CZ#
`add textures etc for the plain here

endwhile

endfunction

+ Code Snippet

do
sync
xeno update
pick screen MOUSEX(),MOUSEY(),0
NONEED = pick object(MOUSEX(),MOUSEY(),0,1000)
MOSX = Get Pick Vector X()+camera position x()
MOSY = Get Pick Vector y()+camera position y()
MOSZ = Get Pick Vector z()+camera position z()
text 50,50,STR$(MOSX)
text 50,100,STR$(MOSY)

drawbox()

loop

//Create box function
Function drawbox()

//get mouse position variables
XORIG=MOUSEX()
YORIG=MOUSEY()

//get screen coordiantes
while Mouseclick()=1
sync

//get screen coordinates
pick screen MOUSEX(),MOUSEY(),0
NONEED = pick object(MOUSEX(),MOUSEY(),0,1000)
MOSX2 = Get Pick Vector X()+camera position x()
MOSY2 = Get Pick Vector y()+camera position y()
MOSZ2 = Get Pick Vector z()+camera position z()
text 50,50,STR$(MOSX)
text 50,100,STR$(MOSY)
text 50,150,STR$(SX#)

`work out the centre of the selected area
CX#=MOSX+(MOSX2-MOSX)*.5
CY#=MOSY+(MOSY2-MOSY)*.5
CZ#=MOSZ+(MOSZ2-MOSZ)*.5

`work out the scale
SX#=abs(MOSX2-MOSX)
SZ#=abs(MOSZ2-MOSZ)

`add the plain object maybe do this every 10th of a second to avoid lag
p=99 `or any free object number
if object exist(p) then delete object p
make object plain p,SX#,SZ#
position object p,CX#,CY#,CZ#
point object p,CX#,CY#+1,CZ#
`add textures etc for the plain here

endwhile

endfunction

I have no idea why this is happening

I can count to banana...

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baxslash

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Posted: 9th Aug 2010 14:06

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I don't get anything from that code, is something missing from it? Where are the objects we are picking using "pick object"?

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Melancholic

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Posted: 9th Aug 2010 14:16

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The only reason "pick object" is in there is because it needs to be called in order to generate the vector data I use mosx, mosy and mosz for. The rest(the function) is basically getting the coordinates of the mouse whilst its being pressed down. The rest is your code to actually create the plane.

I know the code is messy and badly commented, but that’s because I just stripped down my whole program to only that part(though I retained some code so that the pick commands still functioned).

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baxslash

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Posted: 9th Aug 2010 14:20

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My code is often messy and badly commented, that's not what I meant. Try running the code you posted on its own, it doesn't do anything.

Pick object will only return valid data to the pick vector command if you actually pick an object.

I can only assume you haven't run the code you posted exactly as you posted it (not in your game code but exclusive of it).

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Melancholic

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Posted: 9th Aug 2010 16:32 Edited at: 9th Aug 2010 18:25

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I have solved my problem using a different method, which works just fine. Ill provide the code if anyones intrested, though it is messy

+ Code Snippet

//Create box function
Function drawbox()

//get if mouse is clicked
if mouseclick()=1
MOSX = Get Pick Vector X()+camera position x()
MOSY = Get Pick Vector y()+camera position y()
MOSZ = Get Pick Vector z()+camera position z()

//find free object number
NEWOBJ#=FindFreeObjectADV()
make object box NEWOBJ#,2,2,2
position object NEWOBJ#,MOSX,MOSY,MOSZ
texture object NEWOBJ#,1

//set variable values for while loop
scaler=1
scalx=100
scaly=100

while scaler=1
sync

text 50,50,"x:"+STR$(scalx)
text 50,100,"y:"+STR$(scaly)

//add scale values for x
scalx=scalx+MOUSEMOVEX()
//add scale vlaue for y
scaly=scaly+MOUSEMOVEY()

//make sure values dont go negative or too big
if scalx<20
 scalx=20
  endif
if scaly<20
 scaly=20
  endif
if scalx>200
 scalx=200
  endif
if scaly>200
 scaly=200
  endif


//scale object according to mosue movemts
scale object NEWOBJ#,scalx,scaly,100

if MOUSECLICK()=0
scaler=0
endif

endwhile
endif
endfunction

EDIT: Unrelated question here but didnt want to make a new thread. Is there anyway to update a objects scale information as xeno physics seems to be reading the original size and my phyics are messed up. Ive got this code to try fix it

+ Code Snippet

if file exist("temp/object.dbo")=1
delete file "temp/object.dbo"
endif

save object "temp/object.dbo",NEWOBJ#
delete object NEWOBJ#
load object "temp/object.dbo",NEWOBJ#

position object NEWOBJ#,OPOSX,OPOSY,0
xeno make rigid body dynamic box NEWOBJ#

but for some reason i still get the standard cube, im guessing this is also down to not updating the scale info when saving the file

I can count to banana...

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Melancholic

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Posted: 9th Aug 2010 22:43

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Okay, I am sorry for posting so much but i have fixed my problem. Though I am now faced with a much more confusing problem. It might even be a bug. My problem is that DBPro will not recognize any function calls and marks them as syntax errors, i would provide code, but at this point my program is pushing 600 lines.

I have tried both the standard IDE and code surge, any ideas?

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Mobiius

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Posted: 10th Aug 2010 09:50

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Quote: "Is there anyway to update a objects scale information as xeno physics seems to be reading the original size and my phyics are messed up."

Quote: "I am sorry for posting so much but i have fixed my problem."

Do please tell what the fix to this issue is! I'd love to hear it!

My signature is NOT a moderator plaything! Stop changing it!

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Melancholic

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Posted: 10th Aug 2010 10:14 Edited at: 10th Aug 2010 10:15

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All credit goes to Lost In Though and Cash curtis for writing this nice function to replace the scale command. It works in allmost the same way as DBPro's scale command. It supposedly slow but i havent noticed any slow down yet, and im calling it 30 times a second

EDIT: forgot to include link lol http://forum.thegamecreators.com/?m=forum_view&t=111419&b=6

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baxslash

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Posted: 10th Aug 2010 10:36

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That's a great scale code, I've been using it for a while now.

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