BASIC

### Author Topic: 3D Chequerboard in 2D  (Read 3400 times)

#### Brick Redux

• Mr. Drawsprite
• Posts: 60
##### 3D Chequerboard in 2D
« on: 2013-Apr-25 »
Its good to be back guys and here I present a Space Harrier style floor that moves.  Needs work but thats for you lot to deal with.

Cheers.

Mark

Code: GLBasic [Select]
/////////////////////////////////////////////////////////////////////////
//
// 3D Chequerboard in 2D
// A 50p Production
// in association with
// Jelly Babies and some coffee
//

GLOBAL dir, grid, size, jump, scale, ypos, zpos, xpos, tilex[], tiley[], tilez[], polyx[], polyy[]
GLOBAL color, whichcolor, still_free_of_ESC, needsomemorecoffee, andsomemoresugar
GOSUB setup

/////////////////////////////////////////////////////////////////////////
//
// Loop
//
//

WHILE still_free_of_ESC

GOSUB updatethegrid

GOSUB drawthegrid

SHOWSCREEN

WEND

/////////////////////////////////////////////////////////////////////////

SUB drawthegrid:

whichcolor=1

FOR x = 0 TO grid-2

INC whichcolor

IF whichcolor>2
whichcolor=1
ENDIF

color = whichcolor

FOR z = 0 TO grid-2

INC color

IF color>2
color=1
ENDIF

tx = tilex[x][z] / tilez[x][z]
ty = tiley[x][z] / tilez[x][z]

polyx[0]=tx ; polyy[0]=ty

tx = tilex[x+1][z] / tilez[x+1][z]
ty = tiley[x+1][z] / tilez[x+1][z]

polyx[1]=tx ; polyy[1]=ty

tx = tilex[x+1][z+1] / tilez[x+1][z+1]
ty = tiley[x+1][z+1] / tilez[x+1][z+1]

polyx[2]=tx ; polyy[2]=ty

tx = tilex[x][z+1] / tilez[x][z+1]
ty = tiley[x][z+1] / tilez[x][z+1]

polyx[3]=tx ; polyy[3]=ty
//////////////////////////////////////////////////////////////////
// Calculate color depth

ENDIF

IF color = 1
ELSE
ENDIF

///////////////////////////////////////////////////////////////////
// Draw Tile
// cx & cy IN place but NOT used here for manipulating the board - ascend,descend,tilt left/right etc
//

STARTPOLY 0

POLYVECTOR  polyx[0]+cx,polyy[0]+cy,  0, 0,newcol

POLYVECTOR  polyx[1]+cx,polyy[1]+cy,  0, 0,newcol

POLYVECTOR  polyx[2]+cx,polyy[2]+cy,  0, 0,newcol

POLYVECTOR  polyx[3]+cx,polyy[3]+cy,  0, 0,newcol

ENDPOLY

NEXT
NEXT

ENDSUB

SUB updatethegrid:

jump = size / grid

zpos = 8

FOR z = 0 TO grid -1

xpos = scale

FOR x = 0 TO grid -1

tilex[x][z] = xpos
tiley[x][z] = ypos
tilez[x][z] = zpos

xpos = xpos + jump * scale

NEXT

INC zpos , -jump / 20

NEXT

INC size,dir

IF size<160 AND dir=0.1

INC size , 0.1 //....scrolls the board, erm sort of....cough

ELSE

dir=-0.1

ENDIF

IF size>150 AND dir=-0.1

DEC size , 0.1

ELSE

dir=0.1

ENDIF

ENDSUB

SUB setup:

dir=0.1 ; still_free_of_ESC=TRUE

grid = 30 ; size = 150

jump = size / grid ; scale = 25 ; ypos = 400 ; zpos = 8

DIM tilex[grid][grid] ; DIM tiley[grid][grid] ; DIM tilez[grid][grid] ; DIM polyx[9] ; DIM polyy[9]

ENDSUB

ark
A mournful owner of a HP HDX18 Laptop that has died...FECK!

#### mentalthink

• Prof. Inline
• Posts: 3357
• Integrated Brain
##### Re: 3D Chequerboard in 2D
« Reply #1 on: 2013-Apr-26 »
Thanks Mark...

#### Brick Redux

• Mr. Drawsprite
• Posts: 60
##### Re: 3D Chequerboard in 2D
« Reply #2 on: 2013-Apr-26 »

Its a real pleasure just for your replies.

A mournful owner of a HP HDX18 Laptop that has died...FECK!

#### Brick Redux

• Mr. Drawsprite
• Posts: 60
##### Re: 3D Chequerboard in 2D
« Reply #3 on: 2013-Apr-26 »
The cx and cy variables apart from being used to adjust hieght and slope can also produce warp effects to the grid.

One such effect I experimented with left a image similar to swirls/blades of grass.

Polyvector is a very powerful command indeed.
A mournful owner of a HP HDX18 Laptop that has died...FECK!

#### erico

• Community Developer
• Prof. Inline
• Posts: 4177
##### Re: 3D Chequerboard in 2D
« Reply #4 on: 2013-Apr-26 »
I smell lotus around here...

Great snippet, maybe someday I could try a Feedback (msx2) remake with it.

#### Brick Redux

• Mr. Drawsprite
• Posts: 60
##### Re: 3D Chequerboard in 2D
« Reply #5 on: 2013-Apr-26 »
Heres a scrolling version, needs streamlining.

Code: GLBasic [Select]
/////////////////////////////////////////////////////////////////////////
//
// 3D Chequerboard in 2D v.2
//
//
//
//

GLOBAL dir, grid, size, jump, scale, ypos, zpos, xpos, tilex[], tiley[], tilez[], polyx1[], polyy1[]
GLOBAL color, whichcolor, still_free_of_ESC, width, height, polyx2[], polyy2[], newcolor, newcolor1
GETSCREENSIZE width, height
GOSUB setup
GOSUB updatethegrid
/////////////////////////////////////////////////////////////////////////
//
// Loop
//
//

WHILE still_free_of_ESC

GOSUB drawthegrid

SHOWSCREEN

WEND

/////////////////////////////////////////////////////////////////////////

SUB drawthegrid:

whichcolor=1

FOR x = 0 TO grid-2

INC whichcolor

IF whichcolor>2
whichcolor=1
ENDIF

color = whichcolor

FOR z = 0 TO grid-2

INC color

IF color>2
color=1
ENDIF

tx = tilex[x][z] / tilez[x][z]
ty = tiley[x][z] / tilez[x][z]

polyx1[0]=-tx ; polyy1[0]=ty

polyx2[0]=tx ; polyy2[0]=ty

tx = tilex[x+1][z] / tilez[x+1][z]
ty = tiley[x+1][z] / tilez[x+1][z]

polyx1[1]=-tx ; polyy1[1]=ty

polyx2[1]=tx ; polyy2[1]=ty

tx = tilex[x+1][z+1] / tilez[x+1][z+1]
ty = tiley[x+1][z+1] / tilez[x+1][z+1]

polyx1[2]=-tx ; polyy1[2]=ty

polyx2[2]=tx ; polyy2[2]=ty

tx = tilex[x][z+1] / tilez[x][z+1]
ty = tiley[x][z+1] / tilez[x][z+1]

polyx1[3]=-tx; polyy1[3]=ty
polyx2[3]=tx; polyy2[3]=ty
//////////////////////////////////////////////////////////////////
// color

IF color = 1
newcol=RGB(255,255,255)
newcol1=RGB(0,0,180)
ELSE
newcol=RGB(0,0,180)
newcol1=RGB(255,255,255)
ENDIF

///////////////////////////////////////////////////////////////////
// Draw Tile
// cx & cy IN place but NOT used here for manipulating the board - ascend,descend,tilt left/right etc
//

STARTPOLY 0

POLYVECTOR  polyx1[0]+width/2,polyy1[0], 0, 0,newcol

POLYVECTOR  polyx1[1]+width/2,polyy1[1], 0, 0,newcol

POLYVECTOR  polyx1[2]+width/2,polyy1[2], 0, 0,newcol

POLYVECTOR  polyx1[3]+width/2,polyy1[3], 0, 0,newcol

ENDPOLY

STARTPOLY 0

POLYVECTOR  polyx2[0]+width/2,polyy2[0], 0, 0,newcol1

POLYVECTOR  polyx2[1]+width/2,polyy2[1], 0, 0,newcol1

POLYVECTOR  polyx2[2]+width/2,polyy2[2], 0, 0,newcol1

POLYVECTOR  polyx2[3]+width/2,polyy2[3], 0, 0,newcol1

ENDPOLY

NEXT
NEXT
///////////////////////////////////////////////////////////////////
// Scroll the grid
//
FOR z = 0 TO grid -1

FOR x = 0 TO grid -1

IF tilez[x][z]>0.23

DEC tilez[x][z] , 0.02

ELSEIF tilez[x][z]<0.23

tilez[x][z]=0.73 ; GOSUB updatethegrid

ENDIF

NEXT

NEXT

ENDSUB

SUB updatethegrid:

jump = size / grid

zpos = 8

FOR z = 0 TO grid -1

xpos = 10/scale

FOR x = 0 TO grid -1

tilex[x][z] = xpos
tiley[x][z] = ypos
tilez[x][z] = zpos

INC xpos, jump*scale

NEXT

INC zpos , -jump  / 20

NEXT

ENDSUB

SUB setup:

still_free_of_ESC=TRUE

grid = 30 ; size = 150

jump = size / grid ; scale = 35 ; ypos = 500 ; zpos = 8

DIM tilex[grid][grid] ; DIM tiley[grid][grid]
DIM tilez[grid][grid] ; DIM polyx1[9] ; DIM polyy1[9]
DIM polyx2[9] ; DIM polyy2[9]
ENDSUB

A mournful owner of a HP HDX18 Laptop that has died...FECK!