Planet Animation

[Norby]

I am new to GL Basic.  I like to try out different languages.

I created the following program, but when I run the code, the screen appears, then closes.  Nothin appears or happens but it appears and disappears.

Could anyone explain to me what I am doin wrong?

Code (glbasic) Select Expand



// --------------------------------- //
// Project: Time Bot
// Start: Sunday, June 14, 2015
// IDE Version: 12.308
// --------------------------------- //

// Note: Program Uptime: Uptime# = GETTIMERALL()
// PRINT Msg$, X, Y

SEEDRND GETTIMERALL()

SETSCREEN 640, 400, 0
CLEARSCREEN RGB(0, 0, 0)

LOADANIM "Font.png", FontSprite, 8, 16
LOADSPRITE "Sun.png", SunSprite
LOADSPRITE "Moon.png", MoonSprite

// Global Variables
GLOBAL SunSprite=1
GLOBAL MoonSprite=2
GLOBAL FontSprite=3

GLOBAL Angle = 0
GLOBAL Planet = 318
GLOBAL Reds = 0
GLOBAL Greens = 0
GLOBAL Blues = 0
GLOBAL Increment = .004365 * 3
GLOBAL NumStars = 1000

GLOBAL StarRad[]
GLOBAL StarAngle[]

DIM StarRad[NumStars]
DIM StarAngle[NumStars]

LOCAL X, Y
FOR i = 1 TO NumStars
  X = (RND(640) - 320)
  Y = (RND(400) - 200)
  // Convert StarX, StarY
  StarRad[i] = X
  StarAngle[i] = Y
NEXT

GLOBAL StarIncrement = Increment / 5

LOCAL Touch$
LOCAL Quit = 0
WHILE Quit=0
  GOSUB SkyUpdate
  Touch$ = INKEY$()
  IF Touch$="Q" THEN Quit = 1
WEND
END

SUB SkyUpdate:
LOCAL StarX, StarY
LOCAL SunX, SunY
LOCAL MoonX, MoonY
LOCAL Time$, Hours, Minutes, Seconds, Timer

Greens = 255 * .5 * SIN(Angle)
IF Greens < 0 THEN Greens = 0

Blues = 255 * 1 * SIN(Angle)
IF Blues < 0 THEN Blues = 0
DRAWRECT 0, 0, 640, 400, RGB(0, Greens, Blues)

// Rotate AND redraw stars.
FOR i = 1 TO NumStars
   StarX = StarRad[i] * COS(StarAngle[i])
   StarY = StarRad[i] * SIN(StarAngle[i]) - 200
   // Convert X,Y

   SETPIXEL StarX, StarY, RGB(150, 150, 200)
   StarAngle[i] = StarAngle[i] + StarIncrement
NEXT

// Draw the Sun
SunX = Planet * COS(Angle)
SunY = Planet * SIN(Angle) + 158
// Convert X, Y

ZOOMSPRITE SunSprite, SunX, SunY, 2, 2

// Draw the Moon
MoonX = Planet * COS(Angle + 3.14159)
MoonY = Planet * SIN(Angle + 3.14159) + 158
//Convert X, Y

ZOOMSPRITE MoonSprite, MoonX, MoonY, 2, 2

// Roate the sun/moon angle.
Time$ = PLATFORMINFO$("TIME")
Hours# = 3600 * LEFT$(Time$, 2)
Minutes# = 60 * MID$(Time$, 3, 2)
Seconds# = RIGHT$(Time$, 2)
Timer = Hours + Minutes + Seconds

Angle = (2 * 3.14159) * (Timer / 86400) - 3.14159 / 2

SHOWSCREEN
RETURN

ENDSUB



[MrTAToad]

You are getting this error message (well, you would if you ran in debug  mode ) :

bounds: [1000]
access: [1000]
error: 9
"C:\Users\Me\Documents\GLBasic\Test Programs\Test\moo.gbas"(44) error : Out of DIM array

which means you are trying to access part of an array that hasn't been defined.

You should be using :

Code (glbasic) Select Expand

FOR i = 0 TO NumStars-1

for all array accessing (in GLBasic, array indicies start at 0, not 1)[/code]

To start with you'll end up with a program that looks like the included picture.

"How do I get rid of the black bits", I hear you cry.  Quite simple : You have two choices : either add an alpha layer to your graphics, or put

Code (glbasic) Select Expand

SETTRANSPARENCY 0 before your first loading command.

You then end up with the second picture.

[MrTAToad]

By the way, you might be interested in the free Programmer's Reference Guide (and other books) at http://triority.uk/books.html.  You've got until July 12th to download it as I'm closing the website.

[Paul Smith]

Your sites not been  up that long,  if you need your books hosting let me know. I have an old freedom2serve account that still works 5 years after I left.(tiscali and talktalk aquired them and killed them off).

Sent from my M470BSE using Tapatalk

[MrTAToad]

It's been a year now - I'm getting rid of it mainly because I would have to start paying for it

The PRM is available on other sites - free-ebooks
Net being one

[CW]

Thank you for the GLB Programer's Reference Book, MapChap. It is a valuable resource that I will reference often. The section on 3D graphics is especially interesting to me.

-CW

[erico]

Yep, the books are awesome, I bought 2 of them online, digital versions, got both printed locally.

Welcome Norby, was the info helpfull? Did you get around it?

[MrPlow]

Welcome to the Wonderous world of GLB!!

[MrTAToad]

Glad you like the books!

[Ian Price]

Did you scare him off?

[MrTAToad]

Hope not!