What am I doing wrong?

OK - all I want to do is load an image, and be able to pan around on it... I figured I could do this using the crop effect to make a "viewport" to the image. Unfortunately I seem to be braindead, and cannot seem to make this work out. Here's a rough script I've been fiddling with: rebol [] imagefile: %test.gif ;a 320x200 gif imagedata: to-image load imagefile imageoffs: 0x0 imagesize: 160x100 mylayout: layout [ at 0x0 imagedisp: image imagedata rate 15 size 160x100 ] imagedisp/feel: make imagedisp/feel [ engage: func [f a e] [ either imageoffs/x < 100 [ imageoffs/x: imageoffs/x + 1 ][ imageoffs/x: 0 print "back to zero" ] f/effect: [crop imageoffs imagesize] hide/show [imagedisp] show f ] ] view mylayout What am I doing wrong? - Porter Woodward

Hi Porter, I know I've seen a really nice scrolling/zooming demo on a reb site, but I can't find it now. I found a scrolling demo on Code-Conscious/examples, but I know there's more. Maybe someone else will jump in who knows. --Gregg

Gregg Irwin wrote:

>Hi Porter, > >I know I've seen a really nice scrolling/zooming demo on a reb site, but I >can't find it now. I found a scrolling demo on Code-Conscious/examples, but >I know there's more. Maybe someone else will jump in who knows. > >--Gregg >

Petr, thanks, that did it. I guess just "probing" around the layout and face structures a bit more would have revealed it. The /View docs can be so frustrating at times. But, just using img/offset easily allows me to scroll around or animate something without using crop at all. - Porter Woodward

Hi Porter, Was there a reson why were you using the crop effect? You could use the offset of the face .... below is an update to your program to demonstrate (I changed the gif to a png, but you could change it back). rebol [] imagefile: %bigsky.png ;a 320x200 png imagedata: to-image load imagefile imageoffs: 0x0 imagesize: 160x100 mylayout: layout [ at 0x0 imagedisp: image imagedata rate 30 size 160x100 ] imagedisp/feel: make imagedisp/feel [ engage: func [f a e] [ either imageoffs/x < 100 [imageoffs/x: imageoffs/x + 1] [imageoffs/x: 0 print "back to zero"] imagedisp/offset: - imageoffs show imagedisp ] ] view mylayout Cheers Phil === Original Message === OK - all I want to do is load an image, and be able to pan around on it... I figured I could do this using the crop effect to make a "viewport" to the image. Unfortunately I seem to be braindead, and cannot seem to make this work out. Here's a rough script I've been fiddling with: rebol [] imagefile: %test.gif ;a 320x200 gif imagedata: to-image load imagefile imageoffs: 0x0 imagesize: 160x100 mylayout: layout [ at 0x0 imagedisp: image imagedata rate 15 size 160x100 ] imagedisp/feel: make imagedisp/feel [ engage: func [f a e] [ either imageoffs/x < 100 [ imageoffs/x: imageoffs/x + 1 ][ imageoffs/x: 0 print "back to zero" ] f/effect: [crop imageoffs imagesize] hide/show [imagedisp] show f ] ] view mylayout What am I doing wrong? - Porter Woodward