Rem
bbdoc: noddybox.vectorgfx
EndRem
Module noddybox.vectorgfx

ModuleInfo "Framework: 2D Vector Graphics classes"
ModuleInfo "Copyright: Public Domain"
ModuleInfo "Author: Ian Cowburn"
ModuleInfo "Version: $Revision$"

' $Id$

Strict
Import brl.linkedlist
Import brl.math
Import brl.endianstream
Import brl.max2d
Import noddybox.vector
Import noddybox.algorithm

Rem
bbdoc: Defines a method for drawing vector lines
EndRem
Type TVectorGfxLineStyle Abstract
	Rem
	bbdoc: Draws a vector line.
	returns: The or'ed mask of all collision IDs overwritten in @colmap by this line, or zero if @colmap is null.
	about: This routine must draw a line from @x1, @y1 to @x2, @y2 using the colour @r,@g,@b.
	about: @id, @obj and @line must be written into the collision map @colmap if @colmap is not null and @actor is false.
	about: If @colmap is set and @actor true, then collisions must be returned but no points written into the collision map.
	about: If @colmap is set, @actor is true and @list is not null then any collisions should be recorded into this list
	about: (no requirement for duplicate checking).
	about: For an example of creating a line drawing routine view the LineSolid type in the private section of this module.
	EndRem
	Method Draw:Int(x1:Int, y1:Int, x2:Int, y2:Int, r:Int, g:Int, b:Int, id:Int, obj:TVectorGfxObject, line:Int, colmap:TVectorGfxCollisionMap, actor:Int, list:TList) Abstract
End Type

Rem
bbdoc: Set to use solid lines for drawing.
about: This mode draws vector lines as solid colour lines using the current alpha, and is the default mode.
EndRem
Function VectorGfxSetSolid()
	Static.linedraw=New LineSolid
End Function

Rem
bbdoc: Set to use alpha lines for drawing.
about: This mode draws vector lines using a @line_alpha for the lines, except for the end-points drawn with @end_alpha.
EndRem
Function VectorGfxSetAlpha(line_alpha:Double,end_alpha:Double)
	Local l:LineAlpha=New LineAlpha
	l.la=line_alpha
	l.ea=end_alpha
	Static.linedraw=l
End Function

Rem
bbdoc: Set to use thick lines for drawing.
about: This mode draws vector lines using solid line, surrounded by points of alpha @line_alpha.
EndRem
Function VectorGfxSetThickAlpha(line_alpha:Double)
	Local l:ThickAlpha=New ThickAlpha
	l.a=line_alpha
	Static.linedraw=l
End Function

Rem
bbdoc: Set to use a custom drawing method.
EndRem
Function VectorGfxSetCustom(linedraw:TVectorGfxLineStyle)
	Static.linedraw=linedraw
End Function

Rem
bbdoc: Defines a point in the vector graphics collision map.
EndRem
Type TVectorGfxCollision
	Rem
	bbdoc: The X co-ordinate of this collision (in the object co-ordinate space).
	EndRem
	Field	x:Int

	Rem
	bbdoc: The Y co-ordinate of this collision (in the object co-ordinate space).
	EndRem
	Field	y:Int

	Rem
	bbdoc: The collision masks at this point.
	EndRem
	Field	mask:Int

	Rem
	bbdoc: The last vector object that wrote at this point.
	EndRem
	Field	obj:TVectorGfxObject

	Rem
	bbdoc: The index of the line in the last vector object that wrote at this point.
	EndRem
	Field	line:Int
	
	Function Create:TVectorGfxCollision(x:Int, y:Int, mask:Int, obj:TVectorGfxObject, line:Int)
		Local o:TVectorGfxCollision=New TVectorGfxCollision
		o.x=x
		o.y=y
		o.mask=mask
		o.obj=obj
		o.line=line
		Return o
	End Function
End Type


Rem
bbdoc: Defines a vector graphics collision map.
about: Collisions in the library are defined using a bitmask (allowing 32 collision masks).
about: Note that with the way that lines are drawn in an object you are likely
about: to receive collisions for the IDs used by the lines in the object.
EndRem
Type TVectorGfxCollisionMap

	Field width:Int
	Field height:Int
	Field xoff:Int
	Field yoff:Int
	Field data:TVectorGfxCollision[,]

	Rem
	bbdoc: Create a collision map.
	returns: The created collision map.
	about: @width and @height are the size of the collision map.
	EndRem
	Function Create:TVectorGfxCollisionMap(width:Int, height:Int)
		Local o:TVectorGfxCollisionMap=New TVectorGfxCollisionMap
		
		o.width=width
		o.height=height
		o.xoff=0
		o.yoff=0
		o.Clear()
		Return o
	End Function
	
	Rem
	bbdoc: Set the offset of the collision map.
	about: @x and @y are the offsets into the co-ordinate space where the collision map lives.
	EndRem
	Method SetOffset(x:Int, y:Int)
		xoff=x
		yoff=y
	End Method
	
	Rem
	bbdoc: Get a collision point.
	returns: The collision point, or null if nothing drawn there.
	about: @x and @y are the co-ordinates (in the objects co-ordinate space, not the collision map space)
	EndRem
	Method GetCollision:TVectorGfxCollision(x:Int, y:Int)
		If x<xoff Or x>=xoff+width Or y<yoff Or y>=yoff+height
			Return Null
		Else
			Return data[x-xoff,y-yoff]
		EndIf
	End Method
	
	Rem
	bbdoc: Set a collision point.
	returns: The current collision mask for that point, or zero if the point is out of the map's range.
	about: @x and @y are the co-ordinates (in the objects co-ordinate space, not the collision map space)
	EndRem
	Method SetCollision:Int(x:Int, y:Int, id:Int, obj:TVectorGfxObject, line:Int)
		If x<xoff Or x>=xoff+width Or y<yoff Or y>=yoff+height
			Return 0
		EndIf
		
		Local ax:Int=x-xoff
		Local ay:Int=y-yoff
		
		Local cur:TVectorGfxCollision=data[ax,ay]
		
		If Not cur
			cur=TVectorGfxCollision.Create(x,y,id,obj,line)
			data[ax,ay]=cur
		Else
			cur.mask:|id
			cur.obj=obj
			cur.line=line
		EndIf

		Return cur.mask
	End Method
	
	Rem
	bbdoc: Clear the collision map
	EndRem
	Method Clear()
		data=New TVectorGfxCollision[width,height]
	End Method
End Type


Rem
bbdoc: Defines a 2D vector graphics object
EndRem
Type TVectorGfxObject
	Rem
	bbdoc: The points making up this object
	EndRem
	Field points:TVectorGfxPoint[]
	Rem
	bbdoc: The lines making up this object
	EndRem
	Field lines:TVectorGfxLine[]
	Rem
	bbdoc: The X co-ordinate of the object
	EndRem
	Field x:Int
	Rem
	bbdoc: The Y co-ordinate of the object
	EndRem
	Field y:Int
	Rem
	bbdoc: The minimum X co-ordinate of the object.  Only valid after a call to SetPoints().
	EndRem
	Field min_x:Int
	Rem
	bbdoc: The maximum X co-ordinate of the object.  Only valid after a call to SetPoints().
	EndRem
	Field max_x:Int
	Rem
	bbdoc: The minimum Y co-ordinate of the object.  Only valid after a call to SetPoints().
	EndRem
	Field min_y:Int
	Rem
	bbdoc: The maximum Y co-ordinate of the object.  Only valid after a call to SetPoints().
	EndRem
	Field max_y:Int
	Rem
	bbdoc: The width of the object.  Only valid after a call to SetPoints().
	EndRem
	Field width:Int
	Rem
	bbdoc: The height of the object.  Only valid after a call to SetPoints().
	EndRem
	Field height:Int
	Rem
	bbdoc: The angle of the object, as degrees*10.  Must be within the range 0-3599 inclusive.
	EndRem
	Field ang:Int
	Rem
	bbdoc: The scale of the object.
	EndRem
	Field scale:Double

	Field rotated:TVectorGfxPoint[]
	
	Rem
	bbdoc: Creates a new empty object
	returns: The created object.
	EndRem
	Method New()
		points=Null
		lines=Null
		rotated=Null
		x=0
		y=0
		min_x=9999999
		min_y=9999999
		max_x=-9999999
		max_y=-9999999
		width=0
		height=0
		ang=0
		scale=1
	End Method
	
	Rem
	bbdoc: Clones this object
	about: Returns a copy of this object, with its own copy of the line and points.
	EndRem
	Method Clone:TVectorGfxObject()
		Local o:TVectorGfxObject=New TVectorGfxObject
		o.x=x
		o.y=y
		o.min_x=min_x
		o.min_y=min_y
		o.max_x=max_x
		o.max_y=max_y
		o.width=width
		o.height=height
		o.ang=ang
		o.scale=scale
		o.SetPoints(points)
		o.SetLines(lines)
		Return o
	End Method
	
	Rem
	bbdoc: Sets the points for this object
	about: @pa is an array of points for this object.
	EndRem
	Method SetPoints(pa:Object[])
		points=New TVectorGfxPoint[pa.length]
		For Local f:Int=0 Until pa.length
			points[f]=TVectorGfxPoint(pa[f])
			min_x=Min(min_x,points[f].x)
			min_y=Min(min_y,points[f].y)
			max_x=Max(max_x,points[f].x)
			max_y=Max(max_y,points[f].y)
		Next
		width=max_x-min_x
		height=max_y-min_y
	End Method
	
	Rem
	bbdoc: Sets the lines for this object.
	about: @la is the array of lines for this object.
	EndRem
	Method SetLines(la:Object[])
		lines=New TVectorGfxLine[la.length]
		For Local f:Int=0 Until la.length
			lines[f]=TVectorGfxLine(la[f])
		Next
	End Method
	
	Rem
	bbdoc: Whether a point is inside the object
	returns: True if the point lies inside the object.  The object is assumed to be a closed polygon for this test.
	about: @cx, @cy is the point to test.
	about: Calling it before drawing the object will cause runtime errors.
	about: This routine is based on code from comp.graphics.algorithms FAQ 2.03
	EndRem
	Method IsInside:Int(cx:Int, cy:Int)
		Local cross:Int=False
		
		For Local l:TVectorGfxLine=EachIn lines
			Local x1:Int=x+rotated[l.i1].x
			Local y1:Int=y+rotated[l.i1].y
			Local x2:Int=x+rotated[l.i2].x
			Local y2:Int=y+rotated[l.i2].y
			
			If ((((y1<=cy) And (cy<y2)) Or ((y2<=cy) And (cy<y1))) And (cx < (x2 - x1) * (cy - y1) / (y2 - y1) + x1))
				cross=Not cross
			EndIf
		Next
		
		Return cross
	End Method
	
	Rem
	bbdoc: A line's adjusted co-ordinates.
	returns: The rotated and scaled points (in object co-ordinates) of the line.
	about: @i is the index of the line to return the points for.
	about: Calling it before drawing the object will cause runtime errors.
	EndRem
	Method AdjustedCoords:TVectorGfxPoint[](i:Int)
		Local p:TVectorGfxPoint[]=New TVectorGfxPoint[2]
		Local l:TVectorGfxLine=lines[i]
		p[0]=rotated[l.i1]
		p[1]=rotated[l.i2]
		Return p
	End Method
	
	Rem
	bbdoc: A line's normal.
	returns: The normal of the selected line.
	about: @i is the index of the line to return the normal of.  This will return the normal due to the rotation of the object after the object is drawn.
	about: Calling it before drawing the object will cause runtime errors.
	EndRem
	Method Normal:TVector(i:Int)
		Local l:TVectorGfxLine=lines[i]
		Local v:TVector=TVector.Create(rotated[l.i2].y-rotated[l.i1].y,rotated[l.i1].x-rotated[l.i2].x)
		v.Normalise()
		Return v
	End Method
	
	Rem
	bbdoc: Loads the object from the supplied @filename.
	returns: The loaded object, or null if the file could not be opened.
	EndRem
	Function Load:TVectorGfxObject(filename:String)
		Local s:TStream=ReadStream(filename)
		
		If Not s
			Return Null
		EndIf
		
		s=LittleEndianStream(s)
		Local o:TVectorGfxObject=New TVectorGfxObject
		
		o.x=s.ReadInt()
		o.y=s.ReadInt()
		o.ang=s.ReadInt()
		
		Local l:TList=CreateList()
		Local i:Int=s.ReadInt()
		
		For Local f=0 Until i
			l.AddLast(TVectorGfxPoint.Load(s))
		Next
		
		o.SetPoints(l.ToArray())
		
		l.Clear()

		i=s.ReadInt()
		
		For Local f=0 Until i
			l.AddLast(TVectorGfxLine.Load(s))
		Next
		
		o.SetLines(l.ToArray())
		
		s.Close()
		
		Return o
	End Function

	Rem
	bbdoc: Saves the object to the supplied @filename.
	EndRem
	Method Save(filename:String)
		Local s:TStream=WriteStream(filename)
		
		If Not s
			Return Null
		EndIf
		
		s=LittleEndianStream(s)
		
		s.WriteInt(x)
		s.WriteInt(y)
		s.WriteInt(ang)

		s.WriteInt(points.length)
		For Local p:TVectorGfxPoint=EachIn points
			p.Save(s)
		Next
		
		s.WriteInt(lines.length)
		For Local l:TVectorGfxLine=EachIn lines
			l.Save(s)
		Next

		s.Close()
	End Method
	
	Rem
	bbdoc: Draw the object.
	returns: A bitmask of collisions.
	about: Draws the object.  If @colmap is null then no collision processing takes place.
	about: If @actor is true then collision processing takes place, but the object will
	about: not write into the collision map.
	about: If @list is not null then any collisions will be written into this list.  This only applies if @colmap is set and @actor true.
	EndRem
	Method Draw:Int(colmap:TVectorGfxCollisionMap=Null, actor:Int=False, list:TList=Null)
		Local col:Int=0
		
		rotated=New TVectorGfxPoint[points.length]
		
		For Local f:Int=0 Until points.length
			Local p:TAlgoPointD=DoRotateD(points[f].x*scale,points[f].y*scale,ang)
			rotated[f]=TVectorGfxPoint.Create(p.x,p.y)
		Next
		
		Local i:Int=0
		
		For Local l:TVectorGfxLine=EachIn lines
			col:|Static.linedraw.draw(x+rotated[l.i1].x,y+rotated[l.i1].y,x+rotated[l.i2].x,y+rotated[l.i2].y,l.r,l.g,l.b,l.id,Self,i,colmap,actor,list)
			i:+1
		Next
		
		Return col
	End Method
End Type

Rem
bbdoc: Defines a point
EndRem
Type TVectorGfxPoint
	Field x:Int
	Field y:Int
	
	Rem
	bbdoc: Create a point.
	returns: The created point.
	about: @x and @y are the co-ordinates of the point.
	EndRem
	Function Create:TVectorGfxPoint(x:Int, y:Int)
		Local o:TVectorGfxPoint=New TVectorGfxPoint
		o.x=x
		o.y=y
		Return o
	End Function
	
	Function Load:TVectorGfxPoint(s:TStream)
		Local o:TVectorGfxPoint
		o=New TVectorGfxPoint
		o.x=s.ReadInt()
		o.y=s.ReadInt()
		Return o
	End Function
	
	Method Save(s:TStream)
		s.WriteInt(x)
		s.WriteInt(y)
	End Method
End Type

Rem
bbdoc: Defines a line
EndRem
Type TVectorGfxLine
	Field i1:Int
	Field i2:Int
	Field id:Int
	Field r:Int
	Field g:Int
	Field b:Int
	
	Rem
	bbdoc: Create a line.
	returns: The created line.
	about: @i1 and @i2 are the indexes into the point list.  @r, @g and @b is the line's colour.  @id is the collision map mask for the line.
	EndRem
	Function Create:TVectorGfxLine(i1:Int, i2:Int, r:Int, g:Int, b:Int, id:Int)
		Local o:TVectorGfxLine=New TVectorGfxLine
		
		o.i1=i1
		o.i2=i2
		o.r=r
		o.g=g
		o.b=b
		o.id=id
		
		Return o
	End Function
	
	Function Load:TVectorGfxLine(s:TStream)
		Local o:TVectorGfxLine
		o=New TVectorGfxLine
		o.i1=s.ReadInt()
		o.i2=s.ReadInt()
		o.r=s.ReadInt()
		o.g=s.ReadInt()
		o.b=s.ReadInt()
		o.id=s.ReadInt()
		Return o
	End Function
	
	Method Save:TVectorGfxLine(s:TStream)
		s.WriteInt(i1)
		s.WriteInt(i2)
		s.WriteInt(r)
		s.WriteInt(g)
		s.WriteInt(b)
		s.WriteInt(id)
	End Method
End Type

Private

Type Static
	Global linedraw:TVectorGfxLineStyle
	
	Function Init()
		linedraw=New LineSolid
	End Function
End Type

Type LineSolid Extends TVectorGfxLineStyle
	Method Draw:Int(x1:Int, y1:Int, x2:Int, y2:Int, r:Int, g:Int, b:Int, id:Int, obj:TVectorGfxObject, line:Int, colmap:TVectorGfxCollisionMap, actor:Int, list:TList)
		Local mask:Int=0
		Local lp:TList=DoLine(x1,y1,x2,y2)
		
		SetColor(r,g,b)
		
		For Local p:TAlgoPoint=EachIn lp
			If colmap
				If actor
					Local c:TVectorGfxCollision=colmap.GetCollision(p.x,p.y)
					
					If c
						mask:|c.mask
						If list
							list.AddLast(c)
						EndIf
					EndIf
				Else
					mask:|colmap.SetCollision(p.x,p.y,id,obj,line)
				EndIf
			EndIf
			Plot(p.x,p.y)
		Next
		
		Return mask
	End Method
End Type

Type LineAlpha Extends TVectorGfxLineStyle
	Field la:Double
	Field ea:Double
	
	Method Draw:Int(x1:Int, y1:Int, x2:Int, y2:Int, r:Int, g:Int, b:Int, id:Int, obj:TVectorGfxObject, line:Int, colmap:TVectorGfxCollisionMap, actor:Int, list:TList)
		Local mask:Int=0
		Local lp:TList=DoLine(x1,y1,x2,y2)
		Local p:TAlgoPoint
		Local a:Double=GetAlpha()
		
		SetColor(r,g,b)
		SetAlpha(ea)
		
		p=TAlgoPoint(lp.RemoveFirst())
		
		If colmap
			If actor
				Local c:TVectorGfxCollision=colmap.GetCollision(p.x,p.y)
				
				If c
					mask:|c.mask
					If list
						list.AddLast(c)
					EndIf
				EndIf
			Else
				mask:|colmap.SetCollision(p.x,p.y,id,obj,line)
			EndIf
		EndIf
		Plot(p.x,p.y)
		
		If lp.Count()=0
			Return id
		EndIf
		
		p=TAlgoPoint(lp.RemoveLast())
		
		If colmap
			If actor
				Local c:TVectorGfxCollision=colmap.GetCollision(p.x,p.y)
				
				If c
					mask:|c.mask
					If list
						list.AddLast(c)
					EndIf
				EndIf
			Else
				mask:|colmap.SetCollision(p.x,p.y,id,obj,line)
			EndIf
		EndIf
		Plot(p.x,p.y)
		
		SetAlpha(la)

		For Local p:TAlgoPoint=EachIn lp
			If colmap
				If actor
					Local c:TVectorGfxCollision=colmap.GetCollision(p.x,p.y)
					
					If c
						mask:|c.mask
						If list
							list.AddLast(c)
						EndIf
					EndIf
				Else
					mask:|colmap.SetCollision(p.x,p.y,id,obj,line)
				EndIf
			EndIf
			Plot(p.x,p.y)
		Next
		
		SetAlpha(a)
		
		Return mask
	End Method
End Type


Type ThickAlpha Extends TVectorGfxLineStyle
	Field a:Double
	
	Method PlotPoint(x,y)
		SetAlpha(a)
		DrawRect(x-1,y-1,3,3)
		SetAlpha(1.0)
		Plot(x,y)
	End Method
	
	Method Draw:Int(x1:Int, y1:Int, x2:Int, y2:Int, r:Int, g:Int, b:Int, id:Int, obj:TVectorGfxObject, line:Int, colmap:TVectorGfxCollisionMap, actor:Int, list:TList)
		Local mask:Int=0
		Local lp:TList=DoLine(x1,y1,x2,y2)
		
		SetColor(r,g,b)
		
		For Local p:TAlgoPoint=EachIn lp
			If colmap
				If actor
					Local c:TVectorGfxCollision=colmap.GetCollision(p.x,p.y)
					
					If c
						mask:|c.mask
						If list
							list.AddLast(c)
						EndIf
					EndIf
				Else
					mask:|colmap.SetCollision(p.x,p.y,id,obj,line)
				EndIf
			EndIf
			PlotPoint(p.x,p.y)
		Next
		
		Return mask

	End Method
End Type

Static.Init()