Image disappears after a certain amount of time

Blitz3D Forums/Blitz3D Beginners Area/Image disappears after a certain amount of time

OwlEpicurus

(Posted 2009) [#1]

In the game I am programming, I have a function to create text boxes. It works fine most of the time, but if it is continously called for a number of loops through the main program, the image for textbox disappears. It is used as an image buffer, so the program crashes. Here is the code for the function:

Function CreateTextBox(x,y,message$,category,back)

		textbox = CreateImage(600,150)
		
		boxy = y - StringHeight(message$) - 8
		boxx = x
		
		If Len(message$) > 51 And Len(message$) <= 91
			boxheight = 2*StringHeight(message$)+12
			boxwidth = StringWidth(Left(message$,Instr(message$," ",40)))+8 
			
		ElseIf Len(message$) > 91 And Len(message$) <= 131
			boxheight = 3*StringHeight(message$)+16
			
			If Instr(message$," ",40) < Instr(message$," ",80)-Instr(message$," ",40)
				boxwidth = StringWidth(Mid$(message$,Instr(message$," ",40),Instr(message$," ",80)-Instr(message$," ",40)))
			Else 
				boxwidth = StringWidth(Left(message$,Instr(message$," ",40)))+8
			EndIf
			
		Else
			boxheight = StringHeight(message$) + 8
			boxwidth = StringWidth(message$) + 8
		EndIf
							
		SetBuffer ImageBuffer(textbox)
		
		Select category 
			Case 0
				Color 95,235,183
			Case 1	
				Color 185,239,255
			Case 2
				Color 197,213,250
				
		End Select
		Rect 0,0,boxwidth,boxheight
			
		Color 256,256,256

		If Len(message$) > 51

			oldline = Instr(message$," ",40)
			x = 4
			For i = 1 To oldline
				Text x+(i-1)*StringWidth(Mid$(message$,i,1)),4,Mid$(message$,i,1)
			Next
			
			If Len(message$) < 91
				newline1 = Len(message$)
			Else
				newline1 = Instr(message$," ",80)
			EndIf
			
			For i = oldline To newline1
				Text 4+(i-oldline-1)*StringWidth(Mid$(message$,i,1)),18,Mid$(message$,i,1)
			Next
			
			If Len(message$) > 91
				newline2 = Len(message$)
				;newline2 = Instr(message$," ",120)
				For i = newline1 To newline2
					Text 4+(i-newline1-1)*StringWidth(Mid$(message$,i,1)),32,Mid$(message$,i,1)
				Next
			EndIf
			
		Else
		
			Text 4,4,message$
			
		EndIf
		
		SetBuffer BackBuffer()	
		
		If category = 1 Or category = 2
								
			;If category = 2
				;PauseChannel music
			
				;PlaySound sObtainItem\sound
				;Delay 1500
				
				;ResumeChannel music
			
			;EndIf
			
			FlushKeys()
			While Not KeyHit(ENTERKEY)
			
				Cls
				If back = 1
					DrawGraphics(0)
				EndIf
			
				DrawImage textbox,boxx,boxy
			
				Flip
			
			Wend
			
			SetBuffer ImageBuffer(textbox)
			Cls
					
			FlushKeys()
		
		EndIf
		
		If category = 0
			
			DrawImage textbox,boxx,boxy
			
		EndIf

End Function

The image for the textbox is generated only a few lines before it is used for imagebuffer(). As I mentioned earlier the function works fine for the first few minutes worth of loops that it is called up.

Ross C

(Posted 2009) [#2]

The only thing i can think of, without tsting it more thoroughly, is your setting the drawing buffer to the image buffer at the end there, but not setting it back to the backbuffer, for drawing to the main screen again.

Also, your clearing the imagebuffer, with the CLS right after it, which would clear the entire image. Combined with not actually setting back to the BackBuffer(), this may cause your issues.

OwlEpicurus

(Posted 2009) [#3]

That seems to have fixed it. Thanks.