Calling Casaber

BlitzMax Forums/BlitzMax Programming/Calling Casaber

dw817

(Posted 2016) [#1]

I'm having a problem with his virtual screen code.

Now that I'm trying to use it for heavy coding it's not working for what I want.

FRAME STORAGE
0-1=Dialog text & frame (for errors)
2-3=Status text (for showing player status and for showing edit map info)
4-5=Normal text & frame (for gameplay only)
6=Special FX (explosions, spells, etc)
7-8=Combat frame & sprites (may not be needed)
9=Weather (rain, snow, fog, etc)
10=Game Sprites (usually 8-images per)
11=Objects (usually static but can have animation)
12=Tiles (usually static but can also have animation, lowest Z scale)
13=Depth perception image for illusion of height
14-31=custom

In his code, I can see that it does not portray screens where color $000000 (black) is NOT transparent, despite setting flags for it to be so.

Here is a small demonstration. Can someone please post a fix for this ? It's supposed to let the keys of [ and ] erase the original cursor circle and draw a new one.

Instead it is blacking out the area completely opaque.

' Virtual Screen Map Scroller
' Thanks to CASABER for virtual screen code
' The problem. Black ($000000) does not appear as transparent.
' I need it to do so.
Strict
SeedRnd MilliSecs() ' random results each time
SetGraphicsDriver GLMax2DDriver(),0 ' no graphic problems
Graphics 640,480 ' this will be the default size of all virtual screens
glewinit() ' who knows what this does ??
SetBlend(MASKBLEND) ' needed for transparent images
SetMaskColor 0,0,0

Const scrnmax=2 ' Maximum # of virtual screens
Global scrn:TImage[scrnmax],scrnb:timagebuffer[scrnmax] ' keep scrn and scrnb global as they're needed for functions
Global scrnx=GraphicsWidth(),scrny=GraphicsHeight() ' also global
Global pic:TPixmap,pic2:TPixmap

Local i,r,x,y,s=32,os=32

' INIT SCREENS
For i=0 Until scrnmax
  If i=0
    scrn[0]=CreateImage(1024,1024,1,MASKEDIMAGE|DYNAMICIMAGE) ' special case with screen zero
  Else
    scrn[i]=CreateImage(scrnx,scrny,1,MASKEDIMAGE|DYNAMICIMAGE) ' otherwise, same size as screen
  EndIf
  scrnb[i]=timagebuffer.setbuffer(scrn[i])
Next

' // READY TO BEGIN !

waxon 0 ' draw to scrn[0] size 1024x1024
SetLineWidth 8 ' draw thick lines
DrawRect 0,0,1024,1024 ' draw white border to show edges of map
SetColor 0,0,0
DrawRect 4,4,1016,1016
For i=1 To 100 ' colored confetti
  SetColor Rand(192)+64,Rand(192)+64,Rand(192)+64
  DrawOval Rand(1024),Rand(1024),Rand(64)+64,Rand(64)+64
  x=Rand(1024)
  y=Rand(1024)
  DrawLine x,y,x-64+Rand(128),y-64+Rand(128)
  DrawRect Rand(1024),Rand(1024),Rand(64)+64,Rand(64)+64
Next


x=0 ' reset X & Y since we used it above for random confetti
y=0

Repeat '(* MAIN *)
  waxon 1 ' draw now to scrn[1]
    SetColor 1,1,1
    DrawOval 320-s,240-s,s*2,s*2 ' draw black outline for circle
    SetColor 255,255,255
    DrawOval 320-s+2,240-s+2,s*2-4,s*2-4 ' draw the circle inside it
  waxoff
  SetColor 0,0,0
  DrawRect 0,0,640,480
  SetColor 255,255,255
  DrawImage scrn[0],320-x,240-y ' draw our 'map'
  DrawImage scrn[1],0,0 ' draw just the outlined circle
  DrawText "x="+dec$(x,4)+" y="+dec$(y,4),0,0 ' show coordinates
  Flip -1
  If KeyDown(key_left)Then x:-4 ' arrow keys control x & y
  If KeyDown(key_right)Then x:+4
  If KeyDown(key_up)Then y:-4
  If KeyDown(key_down)Then y:+4
  If KeyDown(219)And s>1 Then s:-1
  If KeyDown(221)And s<64 Then s:+1
  If s<>os
    waxon 1
    SetColor 0,0,0
    DrawOval 320-os,240-os,os*2,os*2
    os=s
    waxoff
  EndIf
  waxon 0
  SetColor 255,255,255
  DrawOval Rand(0,1024),Rand(0,1024),32,32
  waxoff
Until KeyDown(key_escape) ' exit on ESCAPE

Function waxon(n)
  waxoff ' ensure only one active writing screen at a time
  scrnb[n].bindbuffer ' this virtual screen is now active
EndFunction

Function waxoff()
  Local i
  For i=0 Until scrnmax
    scrnb[i].unbindbuffer ' release all screens active or not
  Next
EndFunction

Function reset() ' set all graphic changelings to normal
  SetColor 255,255,255
  SetAlpha 1
  SetRotation 0
  SetScale 1,1
  SetLineWidth 1
EndFunction

Function str$(n) ' return value from string
  Return Int(n)
EndFunction

Function dec$(n,m) ' return zero padded number, m is length
	Local r$,i
	If n<0
	  r$="-"
	  m:+1
	EndIf
	For i=Len(str$(n))+1 To m
		r$=r$+"0"
	Next
	r$=r$+str$(Abs(n))
	Return r$
EndFunction

' CRAZY VIRTUAL SCREEN CODE BEGINS HERE -----------------------

Type TImageBuffer
Field Image:TImage ; Field rb:Int[1] ; Field fb:Int[1] ; Field Imageframe:TGLImageframe
Field Frame:Int = 0 ; Field OrigX:Int ; Field OrigY:Int ; Field OrigW:Int ; Field OrigH:Int

Function SetBuffer:TImageBuffer(Image:TImage,Frame:Int = 0)
Local IB:TImageBuffer = New TImageBuffer ; IB.Image = Image ; IB.Frame = Frame ; IB.GenerateFBO() ; IB.BindBuffer() ; Return IB
End Function
	
Method GenerateFBO()
ImageFrame = TGLImageFrame(Image.frame(Frame) ) ; imageframe.v0 = imageframe.v1 ; imageframe.v1 = 0.0
Local W:Int = Image.width ; Local H:Int = Image.Height ; AdjustTexSize(W, H) ; glGenFramebuffersEXT(1, fb)
glGenRenderbuffersEXT(1, rb) ; glBindTexture(GL_TEXTURE_2D, Imageframe.name) ; glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb[0])
glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_COLOR_ATTACHMENT0_EXT, GL_TEXTURE_2D, Imageframe.name, 0)
glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, rb[0]) ; glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT, GL_DEPTH_COMPONENT24, W, H) 
glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT, GL_RENDERBUFFER_EXT, rb[0])
Local status:Int = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT)
End Method
	
Method BindBuffer()
GetViewport(OrigX,OrigY,OrigW,OrigH) ; glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, fb[0])
glMatrixMode GL_PROJECTION ; glLoadIdentity ; glscalef 1.0, -1.0, 1.0 ; glOrtho 0, Image.Width,Image.Height, 0, -1, 1 ; glMatrixMode GL_MODELVIEW
glViewport(0, 0, Image.Width, Image.Height) ; glScissor 0, 0, Image.Width, Image.Height
End Method
	
Method UnBindBuffer()
glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0) ; glMatrixMode GL_PROJECTION ; glLoadIdentity ; glOrtho 0,OrigW, Origh, 0, -1, 1
glMatrixMode GL_MODELVIEW ; glViewport(0, 0, OrigW, OrigH) ; glScissor 0, 0, OrigW, OrigH
End Method

End Type

Function AdjustTexSize(width:Int Var,height:Int Var)
width=Pow2Size(width) ; height=Pow2Size(height)
Repeat
Local t:Int ; glTexImage2D GL_PROXY_TEXTURE_2D,0,4,width,height,0,GL_RGBA,GL_UNSIGNED_BYTE,Null
glGetTexLevelParameteriv GL_PROXY_TEXTURE_2D,0,GL_TEXTURE_WIDTH,Varptr t
If t Return
If width>1 width:/2
If height>1 height:/2
Forever
End Function

Function Pow2Size:Int(n:Int)
Local t:Int=1 ; While t<n ; t:*2; Wend ; Return t
End Function