monkey2/modules/std/graphics/pixmap.monkey2

Namespace std.graphics

#rem monkeydoc Pixmaps allow you to store and manipulate rectangular blocks of pixel data.

A pixmap contains a block of memory used to store a rectangular array of pixels.

#end
Class Pixmap

	#rem monkeydoc @hidden
	#end
	Field OnDiscarded:Void()

	#rem monkeydoc Creates a new pixmap.

	@param width The width of the pixmap in pixels.
	
	@param height The height of the pixmap in pixels.
	
	@param format The pixmap format.
	
	@param data A pointer to the pixmap data.
	
	@param pitch The pitch of the data.
	
	#end
	Method New( width:Int,height:Int,format:PixelFormat=PixelFormat.RGBA32 )

		Local depth:=PixelFormatDepth( format )
		Local pitch:=width*depth
		Local data:=Cast<UByte Ptr>( libc.malloc( pitch*height ) )
		
		_width=width
		_height=height
		_format=format
		_depth=depth
		_data=data
		_pitch=pitch
		OnDiscarded=Lambda()
			libc.free( data )
		End
	End
	
	Method New( width:Int,height:Int,format:PixelFormat,data:UByte Ptr,pitch:Int )
	
		Local depth:=PixelFormatDepth( format )
		
		_width=width
		_height=height
		_format=format
		_depth=depth
		_data=data
		_pitch=pitch
	End

	#rem monkeydoc Releases the memory used by a pixmap.
	
	Memory is only released if the pixmap was created using New, Copy, Convert or Load.
	
	If the pixmap represents a 'window' into another pixmap (ie: it was created using Window) then memory is not released.
	
	Discarding a pixmap also sets its width, height, pitch and depth to 0.
	
	#end
	Method Discard()
		If Not _data Return
		_width=0
		_height=0
		_pitch=0
		_depth=0
		_data=Null
		OnDiscarded()
	End
	
	#rem monkeydoc The pixmap width.
	
	#end
	Property Width:Int()
		Return _width
	End
	
	#rem monkeydoc The pixmap height.
	
	#end
	Property Height:Int()
		Return _height
	End
	
	#rem monkeydoc The pixmap format.
	
	#end
	Property Format:PixelFormat()
		Return _format
	End
	
	#rem monkeydoc The pixmap depth. 
	
	The number of bytes per pixel.
	
	#end
	Property Depth:Int()
		Return _depth
	End
	
	#rem monkeydoc True if pixmap format includes alpha.
	#end
	Property HasAlpha:Bool()
		Select _format
		Case PixelFormat.A8,PixelFormat.IA16,PixelFormat.RGBA32
			Return True
		End
		Return False
	End
	
	#rem monkeydoc The raw pixmap data.
	
	#end
	Property Data:UByte Ptr()
		Return _data
	End
	
	#rem monkeydoc The pixmap pitch.
	
	This is the number of bytes between one row of pixels in the pixmap and the next.
	
	#end
	Property Pitch:Int()
		Return _pitch
	End
	
	#rem monkeydoc Gets a pointer to a pixel in the pixmap.
	
	@param x the x coordinate of the pixel.
	
	@param y the y coordinate of the pixel.
	
	@return the address of the pixel at `x`, `y`.
	
	#end
	Method PixelPtr:UByte Ptr( x:Int,y:Int )
		Return _data + y*_pitch + x*_depth
	End
	
	#rem monkeydoc Sets a pixel to a color.
	
	Sets the pixel at `x`, `y` to `pixel`.
	
	In debug builds, a runtime error will occur if the pixel coordinates lie outside of the pixmap area.
	
	@param x The x coordinate of the pixel.
	
	@param y The y coordinate of the pixel.
	
	@param color The color to set the pixel to.
	
	#end
	Method SetPixel( x:Int,y:Int,color:Color )
		DebugAssert( x>=0 And y>=0 And x<_width And y<_height )
		
		Local p:=PixelPtr( x,y )
		Select _format
		Case Format.A8
			p[0]=color.a * 255
		Case Format.I8
			p[0]=color.r * 255
		Case Format.IA16
			p[0]=color.r * 255
			p[1]=color.a * 255
		Case Format.RGB24
			p[0]=color.r * 255
			p[1]=color.g * 255
			p[2]=color.b * 255
		Case Format.RGBA32
			p[0]=color.r * 255
			p[1]=color.g * 255
			p[2]=color.b * 255
			p[3]=color.a * 255
		Default
			Assert( False )
		End
	End

	#rem monkeydoc Gets the color of a pixel.
	
	Gets the pixel at `x`, `y` and returns it in ARGB format.
	
	In debug builds, a runtime error will occur if the pixel coordinates lie outside of the pixmap area.

	@param x The x coordinate of the pixel.
	
	@param y The y coordinate of the pixel.
	
	@return The color of the pixel at `x`, `y`.
	
	#end
	Method GetPixel:Color( x:Int,y:Int )
		DebugAssert( x>=0 And y>=0 And x<_width And y<_height )
	
		Local p:=PixelPtr( x,y )
		Select _format
		Case Format.A8 
			Return New Color( 0,0,0,p[0]/255.0 )
		Case Format.I8
			Local i:=p[0]/255.0
			Return New Color( i,i,i,1 )
		Case Format.IA16
			Local i:=p[0]/255.0
			Return New Color( i,i,i,p[1]/255.0 )
		Case Format.RGB24
			Return New Color( p[0]/255.0,p[1]/255.0,p[2]/255.0,1 )
		Case Format.RGBA32
			Return New Color( p[0]/255.0,p[1]/255.0,p[2]/255.0,p[3]/255.0 )
		Default
			Assert( False )
		End
		Return Color.None
	End
	
	#rem monkeydoc Sets a pixel to an ARGB color.
	
	Sets the pixel at `x`, `y` to `pixel`.
	
	In debug builds, a runtime error will occur if the pixel coordinates lie outside of the pixmap area.
	
	@param x The x coordinate of the pixel.
	
	@param y The y coordinate of the pixel.
	
	@param color The pixel to set in ARGB format.
	
	#end
	Method SetPixelARGB( x:Int,y:Int,color:UInt )
		DebugAssert( x>=0 And y>=0 And x<_width And y<_height )
	
		Local p:=PixelPtr( x,y )
		Select _format
		Case Format.A8
			p[0]=color Shr 24
		Case Format.I8
			p[0]=color Shr 16
		Case Format.IA16
			p[0]=color Shr 24
			p[1]=color Shr 16
		Case Format.RGB24
			p[0]=color Shr 16
			p[1]=color Shr 8
			p[2]=color
		Case Format.RGBA32
			p[0]=color Shr 16
			p[1]=color Shr 8
			p[2]=color
			p[3]=color Shr 24
		Default
			Assert( False )
		End
	End

	#rem monkeydoc Gets the ARGB color of a pixel.
	
	Get the pixel at `x`, `y` and returns it in ARGB format.

	@param x the x coordinate of the pixel.
	
	@param y the y coordinate of the pixel.
	
	@return the pixel at `x`, `y` in ARGB format.
	
	#end
	Method GetPixelARGB:UInt( x:Int,y:Int )
		DebugAssert( x>=0 And y>=0 And x<_width And y<_height )
	
		Local p:=PixelPtr( x,y )
		Select _format
		Case Format.A8 
			Return p[0] Shl 24
		Case Format.I8 
			Local i:=p[0]
			Return UByte($ff) Shl 24 | i Shl 16 | i Shl 8 | i
		Case Format.IA16
			Local i:=p[1]
			Return p[0] Shl 24 | i Shl 16 | i Shl 8 | i
		Case Format.RGB24
			Return UByte($ff) Shl 24 | p[0] Shl 16 | p[1] Shl 8 | p[2]
		Case Format.RGBA32
			Return p[3] Shl 24 | p[0] Shl 16 | p[1] Shl 8 | p[2]
		Default
			Assert( False )
		End

		Return 0
	End
	
	'Optimize!
	'
	#rem monkeydoc Clears the pixmap to a given color.
	
	@param color The color to clear the pixmap to.
	
	#end
	Method Clear( color:Color )
		For Local y:=0 Until _height
			For Local x:=0 Until _width
				SetPixel( x,y,color )
			Next
		Next
	End
	
	#rem monkeydoc Clears the pixmap to an ARGB color.
	
	@param color ARGB color to clear the pixmap to.
	
	#end
	Method ClearARGB( color:UInt )
		For Local y:=0 Until _height
			For Local x:=0 Until _width
				SetPixelARGB( x,y,color )
			Next
		next
	End
	
	#rem monkeydoc Paste a pixmap to the pixmap.
	
	In debug builds, a runtime error will occur if the operation would write to pixels outside of the pixmap.

	Note: No alpha blending is performed - pixels in the pixmap are simply overwritten.
	
	@param pixmap The pixmap to paste.
	
	@param x The x coordinate.
	
	@param y The y coordinate.
	
	#end
	Method Paste( pixmap:Pixmap,x:Int,y:Int )
		DebugAssert( x>=0 And x+pixmap._width<=_width And y>=0 And y+pixmap._height<=_height )
		
		For Local ty:=0 Until pixmap._height
			For Local tx:=0 Until pixmap._width
				SetPixel( x+tx,y+ty,pixmap.GetPixel( tx,ty ) )
			Next
		Next
	End

	'Optimize!
	'
	#rem monkeydoc Creates a copy of the pixmap.
	
	@return A new pixmap.
	
	#end
	Method Copy:Pixmap()
		Return Convert( _format )
	End

	'Optimize!
	'
	#rem monkeydoc Converts the pixmap to a different format.
	
	@param format The pixel format to convert the pixmap to.
	
	@return A new pixmap.
	
	#end
	Method Convert:Pixmap( format:PixelFormat )
		Local t:=New Pixmap( _width,_height,format )
		For Local y:=0 Until _height
			For Local x:=0 Until _width
				t.SetPixel( x,y,GetPixel( x,y ) )
			Next
		Next
		Return t
	End
	
	'Optimize!
	'
	#rem monkeydoc Premultiply pixmap r,g,b components by alpha.
	#end
	Method PremultiplyAlpha()
		Select _format
		Case PixelFormat.IA16,PixelFormat.RGBA32
			For Local y:=0 Until _height
				For Local x:=0 Until _width
					Local color:=GetPixel( x,y )
					color.r*=color.a
					color.g*=color.a
					color.b*=color.a
					SetPixel( x,y,color )
				Next
			Next
		End
	End
	
	#rem monkeydoc Flips the pixmap on the Y axis.
	#end
	Method FlipY()
		Local sz:=Width*Depth
		Local tmp:=New UByte[sz]
		For Local y:=0 Until Height/2
			Local p1:=PixelPtr( 0,y )
			Local p2:=PixelPtr( 0,Height-1-y )
			libc.memcpy( tmp.Data,p1,sz )
			libc.memcpy( p1,p2,sz )
			libc.memcpy( p2,tmp.Data,sz )
		Next
	End
	
	#rem monkeydoc Returns a rectangular window into the pixmap.
	
	In debug builds, a runtime error will occur if the rectangle lies outside of the pixmap area.
	
	@param x The x coordinate of the top left of the rectangle.

	@param y The y coordinate of the top left of the rectangle.
	
	@param width The width of the rectangle.

	@param height The height of the rectangle.
	
	#end
	Method Window:Pixmap( x:Int,y:Int,width:Int,height:Int )
		DebugAssert( x>=0 And y>=0 And width>=0 And height>=0 And x+width<=_width And y+height<=_height )
		
		Return New Pixmap( width,height,_format,PixelPtr( x,y ),_pitch )
	End
	
	#rem monkeydoc Saves the pixmap to a file.
	
	The only save format currently suppoted is PNG.
	
	#End
	Method Save:Bool( path:String )
	
		Return SavePixmap( Self,path )
	End
	
	#rem monkeydoc Loads a pixmap from a file.
	
	@param path The file path.
	
	@param format The format to load the pixmap in.
	
	@return Null if the file could not be opened, or contained invalid image data.
	
	#end
	Function Load:Pixmap( path:String,format:PixelFormat=PixelFormat.Unknown )
	
		Return LoadPixmap( path,format )
	End
	
	Private
	
	Field _width:Int
	Field _height:Int
	Field _format:PixelFormat
	Field _depth:Int
	Field _data:UByte Ptr
	Field _pitch:Int

End