Hi
I seem to be having problems doing something which should be quite basic. I am just trying to draw a filled 'T' shape using the drawPoly command. However when I draw the coordinates using drawPolyl BlitzMax draws it incorrectly on screen: I don't get a T shape but an asymmetric shape with a diagonal line on the left hand side. As far as I can tell the problem is not with the coordinates I give to drawPoly: When I use the exam same coordinates to draw an outline T (using a series of DrawLine commands) I get the correct shape and no diagonal is present.
I must be doing something wrong with DrawPoly but I have no idea what. Perhaps drawPoly has some a limit on the number of coordinate points you can feed to it (the example 3 point coordinates to draw a filled triangle works fine), or am I misunderstanding something basic about how drawPoly works?
thanks in advance
Here is my code:
Strict
SetGraphicsDriver GLMax2DDriver()
Graphics 800, 600
Const ShapeSize=400
Const ShapeThickness=100
Global scWIdth, scHeight,scCentrex, scCentrey
scWidth = GraphicsWidth(); scHeight = GraphicsHeight(); scCentrex=scWidth / 2; scCentrey=scHeight / 2
While Not KeyHit(key_escape) '0 is pre trial (i.e. START SCREEN)
Cls
DrawTShape(scCentreX,scCentreY,ShapeSize,ShapeThickness)
Flip 1
Wend
Function DrawTShape(x:Int,y:Int,S:Int,tk:Int)
Local pt:Float[8,2] 'pt[i,0]=x coordinate; pt[i,1]= ycoordinate
Local i:Int
pt[0,0]=x-s/2; pt[0,1]=y-s/2
pt[1,0]=x+s/2; pt[1,1]=pt[0,1]
pt[2,0]=pt[1,0]; pt[2,1]=pt[0,1]+tk
pt[3,0]=x+tk/2; pt[3,1]=pt[2,1]
pt[4,0]=pt[3,0]; pt[4,1]=y+s/2
pt[5,0]=x-(tk/2); pt[5,1]=pt[4,1]
pt[6,0]=pt[5,0] pt[6,1]=pt[3,1]
pt[7,0]=pt[0,0]; pt[7,1]=pt[3,1]
Local TShp:Float[]=[ pt[0,0],pt[0,1], pt[1,0],pt[1,1], pt[2,0],pt[2,1] , pt[3,0],pt[3,1], pt[4,0],pt[4,1], pt[5,0],pt[5,1], pt[6,0],pt[6,1], pt[7,0],pt[7,1] ]
'draw a red filled 'T'
SetColor(255,0,0)
DrawPoly TShp
'draw a green outline 'T' at the same location
SetColor(0,255,0)
For i=0 To 6
DrawLine( pt[i,0],pt[i,1], pt[i+1,0],pt[i+1,1] )
Next 'i
DrawLine( pt[7,0],pt[7,1], pt[0,0],pt[0,1] ) 'closes the shape by joining To initial point
EndFunction 'drawTShape
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