ImageViewPort

ImageViewPort ImageNumber, X1, Y1, X2, Y2

Parameters:     ImageNumber = The identifier of this image     X1 = The top left hand X position of the viewport     Y1 = The top left hand Y position of the viewport     X2 = The bottom right hand X position of the viewport     Y2 = The bottom right hand Y position of the viewport

Returns: NONE

ImageViewPort defines the rendering boundaries of an image. These boundaries only take effect when the image is being rendered to, not when it's drawn.       The Viewport is the clipping boundary for the image. Normally when you draw to an image or the screen, our graphics will be clipped to the image/screen edges. What a viewport does, is it allows you to choose a section of the screen/image that you'd like all future drawing operations to be clipped against. This allows us to render graphics to a certain area within an image, without damaging the pixels outside the area. FACTS:       * By default an images viewport will be set to 0,0 to ImageWidth,ImageHeight       * Viewport regions can not exceeed the size of the image.       * Applying a ViewPort to an Image only takes effect when the Image is being rendered to ! (see: RenderToImage)       * To draw a section of image see CopyRect, TextureQuad Mini Tutorial:       Create an image, change it's viewport, and show the effects of the change.       ; First Create an image, colour it blue and draw a red circle on it..   size = 200   CreateImage 1,Size,Size   RenderToImage 1    ; Clear the Image to the bluey colour   Cls RGB(0,100,255)    ; Set the Images Viewport (clipping area) so that it's  50 pixels inside it's size   ImageViewPort 1,50,50,Size-50,size-50    ; Clear the image (clipped to the view port) to a green colour   Cls RGB(0,200,0)    ; Draw a bunch of circles to this image..   For lp =0 To 100      CircleC Rnd(Size),Rnd(Size),Rnd(10),1,RndRGB()   Next    ; redirect all drawing to the Screen   RenderToScreen       ;  Draw this image as a solid image.   DrawImage 1,100,100,0    ; Display the Pixel coordinates of the images Viewport   Print "Images ViewPort X1:"+Str$(GetImageViewPortX1(1))   Print "Images ViewPort Y1:"+Str$(GetImageViewPortY1(1))   Print "Images ViewPort X2:"+Str$(GetImageViewPortX2(1))   Print "Images ViewPort Y2:"+Str$(GetImageViewPortY2(1))    ; Display the Screen and wait for the user to press a key   Sync   WaitKey       This example would output.      Images ViewPort X1: 50   Images ViewPort Y1: 50   Images ViewPort X2: 150   Images ViewPort Y2: 150

Related Info:	GetImageViewPortX1 | GetImageViewPortX2 | GetImageViewPortY1 | GetImageViewPortY2 :

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