Camera Orientated Rotation - GameCreators Forum

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= HighXplosive =

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Posted: 23rd Nov 2005 22:06

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Hello.

This is my first post on the forum: I'm in a rather dire situation. I'm having trouble making the camera rotate around an object (like the earth orbiting the sun). I've experimented with all the camera commands but to no avail. This program is for my computing project in Advanced Higher (Scotland). The game theory is outlined below.

Problem solving in Dark Basic has been most enjoyable, but I am stuck. I have included the source code. Anyone up for explaining to me how to do it and enlightening me as to why that method works? Efficiency is not very important as of yet, so doesn't matter if the code is large. It's the complexity that needs explaining. In fact, the more inefficient my code is, the more I can Evaluate in my project Evalutation stage

.

Game Theory (Or Design):

3D Noughts and Crosses, a 3 x 3 x 3 cube. The textures change to X or O on each cube to represent the state. Once 3 cubes are aligned as X or O that counts as 3 in a row. The Camera should rotate around the central cube, allowing all cubes to be seen. Opacity and transparency can be included if necessary to see central cube. 2 Players click on the cubes in turn to play. Nothing fancy. The final solution must include file handling and search OR sorting algorithms. I intend to code these in using game saving or score saving and score sorting etc.

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= HighXplosive =

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Posted: 24th Nov 2005 00:22

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For some reason the source code didn't post correctly I think. I'm attaching it to this post again to see if it works.

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= HighXplosive =

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Posted: 24th Nov 2005 12:21

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:\ The source code didn't appear again: I'm going to post it within the post instead. Hope the forum formatting doesn't mess it up.

Rem Project: AH Computing Project
Rem Created: 23/11/2005 16:13:37

Rem ***** Main Source File *****

` FOR LOOPs to create 27 aligned cubes spaced 100 units from each other in a 3 x 3 x 3
` formation. (Prototype for 3D Noughts and Crosses). x co - ord used to alter position.
` Linea1 is cube 1 to 3, i.e the first 3 cubes at the bottom of a 3 by 3 by 3 cube closest
` to the camera. Line a2 is the next 3 cubes behind Linea1. Lineb1 is 100 Y co-ordinates
` above Linea1. No concise as of yet for clarity.

x = 0
for linea1 = 1 to 3
make object cube linea1,50
position object linea1, x, 0, 0
x = x + 100
next linea1

x = 0
for linea2 = 4 to 6
make object cube linea2,50
position object linea2, x, 0, 100
x = x + 100
next linea2

x = 0
for linea3 = 7 to 9
make object cube linea3,50
position object linea3, x, 0, 200
x = x + 100
next linea3

x = 0
for lineb1 = 10 to 12
make object cube lineb1,50
position object lineb1, x, 100, 0
x = x + 100
next lineb1

x = 0
for lineb2 = 13 to 15
make object cube lineb2,50
position object lineb2, x, 100, 100
x = x + 100
next lineb2

x = 0
for lineb3 = 16 to 18
make object cube lineb3,50
position object lineb3, x, 100, 200
x = x + 100
next lineb3

x = 0
for linec1 = 19 to 21
make object cube linec1,50
position object linec1, x, 200, 0
x = x + 100
next linec1

x = 0
for linec2 = 22 to 24
make object cube linec2,50
position object linec2, x, 200, 100
x = x + 100
next linec2

x = 0
for linec3 = 25 to 27
make object cube linec3,50
position object linec3, x, 200, 200
x = x + 100
next linec3

` End of cube creation.

`Position camera away from cubes  and deviated slightly by 70 (x Co-ord) to see all cubes).
position camera 170,100,-400
`position camera 100, 100, -400 (Final camera positioning once rotation complete.)
`Point the camera at the central cube (object 14), co-ord 100,100,100
point camera 100,100,100

`Sync setup
sync on
sync rate 30

`Main loop
do

`Return X and Y values setup.
camXcord# = camera position X()
camYcord# = camera position Y()

if leftkey () = 1 then `rotate around the central cube going clockwise, y rotation.
if rightkey () = 1 then `rotate around the central cube going anti-clockwise, y rotation.
if upkey () = 1 then `rotate around the central cube, x rotation upwards.
if downkey () = 1 then `rotate around the central cube, x rotation downwards.

Remstart
This is where I'm stuck: I can't get the camera to rotate around object 14
(the central cube). The camera pans left right etc using several commands, such
as x and y rotation, meaning it "looks" away from the central cube.
Remend

sync
loop

`End of program

remstart : Work in progress code and experimentation.

position camera (caX#-5),(caY#-5),-400
point camera 100,100,100

` object rotation prototype

caY# = object angle Y(1)
caX# = object angle X(1)
caZ# = object angle Z(1)

if leftkey () = 1 then
for objectnumberleftkeyloop = 1 to 27
yrotate object (objectnumberleftkeyloop),(caY#+5)
next objectnumberleftkeyloop

if rightkey () = 1 then
for objectnumberrightkeyloop = 1 to 27
yrotate object (objectnumberrightkeyloop),(caY#-5)
next objectnumberrightkeyloop

if upkey () = 1 then
for objectnumberupkeyloop = 1 to 27
xrotate object (objectnumberupkeyloop),(caX#-5)
next objectnumberupkeyloop

if downkey () = 1 then
for objectnumberdownkeyloop = 1 to 27
xrotate object (objectnumberdownkeyloop),(caX#+5)
next objectnumberdownkeyloop

` prototype camera functions

caY# = camera angle Y()
 if leftkey () = 1 then xrotate camera wrapvalue (caY#-5)
 if rightkey () = 1 then xrotate camera wrapvalue (caY#+5)

if upkey() = 1 then move camera 10
  if downkey() = 1 then move camera -10

`end of prototype camera functions

+ Code Snippet

Rem Project: AH Computing Project
Rem Created: 23/11/2005 16:13:37

Rem ***** Main Source File *****

` FOR LOOPs to create 27 aligned cubes spaced 100 units from each other in a 3 x 3 x 3
` formation. (Prototype for 3D Noughts and Crosses). x co - ord used to alter position.
` Linea1 is cube 1 to 3, i.e the first 3 cubes at the bottom of a 3 by 3 by 3 cube closest
` to the camera. Line a2 is the next 3 cubes behind Linea1. Lineb1 is 100 Y co-ordinates
` above Linea1. No concise as of yet for clarity.

x = 0
for linea1 = 1 to 3
make object cube linea1,50
position object linea1, x, 0, 0
x = x + 100
next linea1

x = 0
for linea2 = 4 to 6
make object cube linea2,50
position object linea2, x, 0, 100
x = x + 100
next linea2

x = 0
for linea3 = 7 to 9
make object cube linea3,50
position object linea3, x, 0, 200
x = x + 100
next linea3

x = 0
for lineb1 = 10 to 12
make object cube lineb1,50
position object lineb1, x, 100, 0
x = x + 100
next lineb1

x = 0
for lineb2 = 13 to 15
make object cube lineb2,50
position object lineb2, x, 100, 100
x = x + 100
next lineb2

x = 0
for lineb3 = 16 to 18
make object cube lineb3,50
position object lineb3, x, 100, 200
x = x + 100
next lineb3

x = 0
for linec1 = 19 to 21
make object cube linec1,50
position object linec1, x, 200, 0
x = x + 100
next linec1

x = 0
for linec2 = 22 to 24
make object cube linec2,50
position object linec2, x, 200, 100
x = x + 100
next linec2

x = 0
for linec3 = 25 to 27
make object cube linec3,50
position object linec3, x, 200, 200
x = x + 100
next linec3

` End of cube creation.


`Position camera away from cubes  and deviated slightly by 70 (x Co-ord) to see all cubes).
position camera 170,100,-400
`position camera 100, 100, -400 (Final camera positioning once rotation complete.)
`Point the camera at the central cube (object 14), co-ord 100,100,100
point camera 100,100,100

`Sync setup
sync on
sync rate 30

`Main loop
do

`Return X and Y values setup.
camXcord# = camera position X()
camYcord# = camera position Y()

if leftkey () = 1 then `rotate around the central cube going clockwise, y rotation.
if rightkey () = 1 then `rotate around the central cube going anti-clockwise, y rotation.
if upkey () = 1 then `rotate around the central cube, x rotation upwards.
if downkey () = 1 then `rotate around the central cube, x rotation downwards.

Remstart
This is where I'm stuck: I can't get the camera to rotate around object 14
(the central cube). The camera pans left right etc using several commands, such
as x and y rotation, meaning it "looks" away from the central cube.
Remend


sync
loop

`End of program


remstart : Work in progress code and experimentation.

position camera (caX#-5),(caY#-5),-400
point camera 100,100,100

` object rotation prototype

caY# = object angle Y(1)
caX# = object angle X(1)
caZ# = object angle Z(1)

if leftkey () = 1 then
for objectnumberleftkeyloop = 1 to 27
yrotate object (objectnumberleftkeyloop),(caY#+5)
next objectnumberleftkeyloop

if rightkey () = 1 then
for objectnumberrightkeyloop = 1 to 27
yrotate object (objectnumberrightkeyloop),(caY#-5)
next objectnumberrightkeyloop

if upkey () = 1 then
for objectnumberupkeyloop = 1 to 27
xrotate object (objectnumberupkeyloop),(caX#-5)
next objectnumberupkeyloop

if downkey () = 1 then
for objectnumberdownkeyloop = 1 to 27
xrotate object (objectnumberdownkeyloop),(caX#+5)
next objectnumberdownkeyloop

` prototype camera functions

caY# = camera angle Y()
 if leftkey () = 1 then xrotate camera wrapvalue (caY#-5)
 if rightkey () = 1 then xrotate camera wrapvalue (caY#+5)

 if upkey() = 1 then move camera 10
  if downkey() = 1 then move camera -10

 `end of prototype camera functions

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RUCCUS

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Location: Canada

Posted: 24th Nov 2005 13:51

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Ta-Daa:

SYNC ON:SYNC RATE 0:AUTOCAM OFF:HIDE MOUSE

`Make the Earth
MAKE OBJECT SPHERE 1,50

`Make the Sun
MAKE OBJECT SPHERE 2,300

`Make a "dummy" object, it wont be seen
MAKE OBJECT TRIANGLE 3,0,0,0,0,0,0,0,0,0

`Now add a limb to the dummy object, using a mesh made from the dummy object since the limb wont be seen either, its purely for positioning purposes

MAKE MESH FROM OBJECT 1,3
ADD LIMB 3,1,1
OFFSET LIMB 3,1,0,0,-600
DELETE MESH 1

`Color the sun yellow, the Earth blue and the backdrop black, for cosmetic purposes

COLOR OBJECT 1,RGB(000,000,255)
COLOR OBJECT 2,RGB(255,255,000)
COLOR BACKDROP RGB(000,000,000)

`Position the camera so we can see whats happening

POSITION CAMERA 0,900,-900
POINT CAMERA 0,0,0

`Start the main loop

DO

`Rotate the dummy object on the y axis .1 degrees each loop

YROTATE OBJECT 3,WRAPVALUE(OBJECT ANGLE Y(3)+.1)

`Position the Earth object at the dummys limb positions each loop, this will then give the effect of the earth rotating around the object.

POSITION OBJECT 1, LIMB POSITION X(3,1),LIMB POSITION Y(3,1), LIMB POSITION Z(3,1)

`Now display some fanciful text for no reason at all
CENTER TEXT SCREEN WIDTH()/2,0, "Earth...Orbiting Sun... Thingy... o.O"

`Refresh the screen and end the loop

SYNC
LOOP

+ Code Snippet

SYNC ON:SYNC RATE 0:AUTOCAM OFF:HIDE MOUSE

`Make the Earth
MAKE OBJECT SPHERE 1,50

`Make the Sun
MAKE OBJECT SPHERE 2,300

`Make a "dummy" object, it wont be seen
MAKE OBJECT TRIANGLE 3,0,0,0,0,0,0,0,0,0

`Now add a limb to the dummy object, using a mesh made from the dummy object since the limb wont be seen either, its purely for positioning purposes

MAKE MESH FROM OBJECT 1,3
ADD LIMB 3,1,1
OFFSET LIMB 3,1,0,0,-600
DELETE MESH 1

`Color the sun yellow, the Earth blue and the backdrop black, for cosmetic purposes

COLOR OBJECT 1,RGB(000,000,255)
COLOR OBJECT 2,RGB(255,255,000)
COLOR BACKDROP RGB(000,000,000)

`Position the camera so we can see whats happening

POSITION CAMERA 0,900,-900
POINT CAMERA 0,0,0

`Start the main loop

DO

`Rotate the dummy object on the y axis .1 degrees each loop

YROTATE OBJECT 3,WRAPVALUE(OBJECT ANGLE Y(3)+.1)

`Position the Earth object at the dummys limb positions each loop, this will then give the effect of the earth rotating around the object.

POSITION OBJECT 1, LIMB POSITION X(3,1),LIMB POSITION Y(3,1), LIMB POSITION Z(3,1)

`Now display some fanciful text for no reason at all
CENTER TEXT SCREEN WIDTH()/2,0, "Earth...Orbiting Sun... Thingy... o.O"

`Refresh the screen and end the loop

SYNC
LOOP

This is just an example, replace the sun with whatever object you want the camera to be pointing at, and instead of making the earth positioned at the limb put the camera there and point the camera towards the sun.

- RUCCUS

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= HighXplosive =

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Posted: 24th Nov 2005 17:59

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Thank you for that. It was very useful in helping my understand the rotation of objects around each other. But it's not what I'm trying to solve.

I need to get a camera to rotate around the object: so instead of an "earth" it would be a camera. That camera needs to face the "sun" as well. I also slightly confused about limbs and the wrapvalue command. Can you enlighten me on them?

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Scorpyo

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Posted: 24th Nov 2005 22:53

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Nothing to do with your case but the code has subroutines (camera_control and update_camera) that include rotation around the character (cone) by pressing b or n.
you can easily put the arrows in place of the letters.
The main camera routine is update_camera
The secret is to point the camera to the object (position) you want to rotate around. (in this case, the cone)
Run the code below, You may get some ideas to get applied to your code.
cheers

Rem * Title  : pick
Rem * Author  : Scorpyo

rem **********  MAIN 1  ****************
set display mode 800,600,16
hide mouse
sync on
backdrop on
grid=30
mtxrandomize=1
landsize=20000
x#=10000
gosub Setupland1
gosub makecubes
gosub Character
gosub resetcam
rem set global collision off
sync rate 60
set camera range 1,10000
set object collision to boxes 9999
rem set camera fov 120
rem *****MAIN LOOP******

do

rem check borders
 if x#<100 then x#=100
 if x#>landsize-100 then x#=landsize-100
 if z#<100 then z#=100
 if z#>landsize-100 then z#=landsize-100

gosub Playercontrol
rem call to camera changes subroutine ( bottom key row )
 gosub camera_controls
 rem Calculate position data
 oldx#=x#
 oldz#=z#
 x#=newxvalue(x#,a#,s#)
 z#=newzvalue(z#,a#,s#)

rem calls camera update subroutine
 gosub update_camera
 gosub printdata
 gosub pickchairs
rem Update active model (yflag adds height of the current floor/object)
 h#=get ground height(1,x#,z#)
 position object 9999,x#,h#+5,z#
 yrotate object 9999,a#
rem Update screen
 sync

rem End loop
loop

rem ** SUBROUTINES ***************************
pickchairs:
if holding=1 and mouseclick()=2 then holding=0:wait 50
For chair = 1 to 20
   if object collision (9999,chair) and mouseclick()=1 and holding=0
   holding=1:chairflag=chair
   endif
   if holding=1 then position object chairflag,x#,50,z#
Next chair
return
rem ****** CREATE LEVEL ******
Setupland1:
make matrix 1,landsize,landsize,grid,grid
randomize matrix 1,mtxrandomize
update matrix 1
return

rem ***** PLAYERCONTROL *****
Playercontrol:
rem ****Character walk ****
 if upkey()=1 and s#<12 then s#=s#+0.5
 if downkey()=1 and s#>-12 then s#=s#-0.5
 if leftkey()=1 then a#=wrapvalue(a#-1)
 if rightkey()=1 then a#=wrapvalue(a#+1)
return

rem ****BUILD PLAYER****
rem object 9999
Character:
rem make cone
 make object cone 9999,100
 scale object 9999,80,100,140
rem point tip forward
 xrotate object 9999,60
 set object cull 9999,0
return
camera_controls:
if inkey$()="z" then camdist=camdist+2
if inkey$()="x" then camdist=camdist-2
if inkey$()="b" then camrot=camrot+2
if inkey$()="n" then camrot=camrot-2
if inkey$()="c" then camhgt=camhgt+2
if inkey$()="v" then camhgt=camhgt-2
if inkey$()="m" then camlen=camlen+2
if inkey$()="," then camrot = 180
if inkey$()="." then gosub Resetcam
return
rem camera update
update_camera:
rem Position camera to the back of the character
cx#=newxvalue(x#,wrapvalue(a#+camrot),camdist)
cz#=newzvalue(z#,wrapvalue(a#+camrot),camdist)
cy#=get ground height(1,cx#,cz#)
position camera cx#,cy#+camhgt,cz#
rem Point camera at object
point camera x#,y#+camlen,z#
return
 rem camera reset
Resetcam:
camdist=-400
camhgt=400
camrot=0
camlen=200
return
printdata:
set cursor 0,0
print "holding=",holding
print "Left mouse = Pick"
print "Right mouse = Drop"
return
makecubes:
for n=1 to 20
make object cube n,100
cx#=rnd(20000):cz#=rnd(20000)
position object n,cx#,50,cz#
set object collision to polygons n
next n
return

+ Code Snippet

Rem * Title  : pick
Rem * Author  : Scorpyo

rem **********  MAIN 1  ****************
set display mode 800,600,16
hide mouse
sync on
backdrop on
grid=30
mtxrandomize=1
landsize=20000
x#=10000
gosub Setupland1
gosub makecubes
gosub Character
gosub resetcam
rem set global collision off
sync rate 60
set camera range 1,10000
set object collision to boxes 9999
rem set camera fov 120
rem *****MAIN LOOP******

do

rem check borders
 if x#<100 then x#=100
 if x#>landsize-100 then x#=landsize-100
 if z#<100 then z#=100
 if z#>landsize-100 then z#=landsize-100

gosub Playercontrol
rem call to camera changes subroutine ( bottom key row )
 gosub camera_controls
 rem Calculate position data
 oldx#=x#
 oldz#=z#
 x#=newxvalue(x#,a#,s#)
 z#=newzvalue(z#,a#,s#)

rem calls camera update subroutine
 gosub update_camera
 gosub printdata
 gosub pickchairs
rem Update active model (yflag adds height of the current floor/object)
 h#=get ground height(1,x#,z#)
 position object 9999,x#,h#+5,z#
 yrotate object 9999,a#
rem Update screen
 sync

rem End loop
loop

rem ** SUBROUTINES ***************************
pickchairs:
if holding=1 and mouseclick()=2 then holding=0:wait 50
For chair = 1 to 20
   if object collision (9999,chair) and mouseclick()=1 and holding=0
   holding=1:chairflag=chair
   endif
   if holding=1 then position object chairflag,x#,50,z#
Next chair
return
rem ****** CREATE LEVEL ******
Setupland1:
make matrix 1,landsize,landsize,grid,grid
randomize matrix 1,mtxrandomize
update matrix 1
return

rem ***** PLAYERCONTROL *****
Playercontrol:
rem ****Character walk ****
 if upkey()=1 and s#<12 then s#=s#+0.5
 if downkey()=1 and s#>-12 then s#=s#-0.5
 if leftkey()=1 then a#=wrapvalue(a#-1)
 if rightkey()=1 then a#=wrapvalue(a#+1)
return

rem ****BUILD PLAYER****
rem object 9999
Character:
rem make cone
 make object cone 9999,100
 scale object 9999,80,100,140
rem point tip forward
 xrotate object 9999,60
 set object cull 9999,0
return
camera_controls:
if inkey$()="z" then camdist=camdist+2
if inkey$()="x" then camdist=camdist-2
if inkey$()="b" then camrot=camrot+2
if inkey$()="n" then camrot=camrot-2
if inkey$()="c" then camhgt=camhgt+2
if inkey$()="v" then camhgt=camhgt-2
if inkey$()="m" then camlen=camlen+2
if inkey$()="," then camrot = 180
if inkey$()="." then gosub Resetcam
return
rem camera update
update_camera:
rem Position camera to the back of the character
cx#=newxvalue(x#,wrapvalue(a#+camrot),camdist)
cz#=newzvalue(z#,wrapvalue(a#+camrot),camdist)
cy#=get ground height(1,cx#,cz#)
position camera cx#,cy#+camhgt,cz#
rem Point camera at object
point camera x#,y#+camlen,z#
return
 rem camera reset
Resetcam:
camdist=-400
camhgt=400
camrot=0
camlen=200
return
printdata:
set cursor 0,0
print "holding=",holding
print "Left mouse = Pick"
print "Right mouse = Drop"
return
makecubes:
for n=1 to 20
make object cube n,100
cx#=rnd(20000):cz#=rnd(20000)
position object n,cx#,50,cz#
set object collision to polygons n
next n
return

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RUCCUS

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Posted: 24th Nov 2005 22:59

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Which is what I said, Im not going to give you the entire answer I want you to do some work. So like I said, replace the earth with the camera, and use point camera to point the camera toward the sun, replace the sun with whatever you want it to rotate around.

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= HighXplosive =

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Posted: 25th Nov 2005 12:40

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Woops. Pardon me, I didn't notice the part about the camera in your post Ruccus. Okay, thanks for this you two: I'll mess about with it to see if it works then reply back.

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= HighXplosive =

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Posted: 26th Nov 2005 18:58

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I've integrated Ruccus' code into mine so that it works with it. It's working, but not precisely to my requirements. I have tinkered with the values, but I don't understand or know how to make it work the way I want it to. If you run the code first, I'll describe the problem. The only working function is the left key so far.