Thanks! I guess it is time to set up a GitHub repo for stuff I work on. I think this would be a good thing to post as a behavior stack only script. On Sat, Jan 27, 2018 at 1:48 PM Richard Gaskin via use-livecode < use-livecode@lists.runrev.com> wrote:
> Brian Milby wrote: > > > Here's what I came up with. It is a little slow though. It's pretty > > much a port of the code that I linked. I had to adapt to the way move > > events are issued in LC (particularly that a touch start does not > > include coordinates). I also added the ability to continue moving > > when a zoom stops (only one touch ended). I initially was calling the > > "updateImage" handler using send in time (and checking pending > > messages to avoid calling multiple times), but the code is fast enough > > to not benefit from that (adding delay made it less smooth, the > > "updateImage" handler always seemed to finish before another move > > event was queued). > > > > I put the code in the graphic. I called the "initGraphic" handler > > from the card preOpenCard handler. > > Very kind of you, Brian. Thanks! Much obliged. > > I just gave it a whirl and it seems to work rather well. MUCH better > for me than embedding an entire browser app inside my app just to get a > good pinch. > > Since I was working on an image rather than a graphic, I modded the > script to use a script-local object specifier rather than the hard-wired > graphic reference, then added a mouseDown handler to trigger your init > so I could test it easily. > > While I was at it I re-wrapped a few things to hopefully fit better here > for others to easily copy-n-paste. > > Thanks again - it's nicely done. > > @Michael Doub: another candidate for MasterLib? > > -- > Richard Gaskin > Fourth World Systems > > > ------ > > > local panning, \ > zooming, \ > startX0, startY0, \ > startX1, startY1, \ > endX0, endY0, \ > endX1, endY1, \ > startDistanceBetweenFingers, \ > endDistanceBetweenFingers, \ > pinchRatio, \ > imgWidth, imgHeight, \ > currentContinuousZoom, \ > currentOffsetX, currentOffsetY, \ > currentWidth, currentHeight, \ > newContinuousZoom, \ > newHeight, newWidth, \ > newOffsetX, newOffsetY, \ > centerPointStartX, centerPointStartY, \ > centerPointEndX, centerPointEndY, \ > translateFromZoomingX, translateFromZoomingY, \ > translateFromTranslatingX, translateFromTranslatingY, \ > translateTotalX, translateTotalY, \ > percentageOfImageAtPinchPointX, \ > percentageOfImageAtPinchPointY, \ > sTouchArray, sTouch0, sTouch1 > > local sZoomObj > > on mouseDown > put the long id of me into sZoomObj -- Change this to specify object > initGraphic > end mouseDown > > > on initGraphic > local tLoc > put the width of sZoomObj into imgWidth > put the height of sZoomObj into imgHeight > put 1.0 into currentContinuousZoom > put the left of sZoomObj into currentOffsetX > put the top of sZoomObj into currentOffsetY > put imgWidth into currentWidth > put imgHeight into currentHeight > end initGraphic > > on touchMove pID, pX, pY > -- capture current position > put pX into sTouchArray[pID]["x"] > put pY into sTouchArray[pID]["y"] > > -- since the touch start doesn't include location, need to handle > -- the calculations here > if sTouchArray[pID]["started"] is empty then > put true into sTouchArray[pID]["started"] > if the number of lines of the keys of sTouchArray is 1 then > put pID into sTouch0 > put pX into startX0 > put pY into startY0 > else if the number of lines of the keys of sTouchArray is 2 then > put pID into sTouch1 > put sTouchArray[sTouch0]["x"] into startX0 > put sTouchArray[sTouch0]["y"] into startY0 > put pX into startX1 > put pY into startY1 > put ((startX0 + startX1) / 2.0) into centerPointStartX > put ((startY0 + startY1) / 2.0) into centerPointStartY > put (centerPointStartX - currentOffsetX) / currentWidth \ > into percentageOfImageAtPinchPointX > put (centerPointStartY - currentOffsetY) / currentHeight \ > into percentageOfImageAtPinchPointY > put sqrt((startX1-startX0)^2 + (startY1-startY0)^2) \ > into startDistanceBetweenFingers > end if > updatePanZoomState > exit touchMove > end if > > -- record the end touch locations for the move > if panning then > put pX into endX0 > put pY into endY0 > else if zooming then > put sTouchArray[sTouch0]["x"] into endX0 > put sTouchArray[sTouch0]["y"] into endY0 > put sTouchArray[sTouch1]["x"] into endX1 > put sTouchArray[sTouch1]["y"] into endY1 > end if > > updateImage > end touchMove > > on touchEnd pID > put true into sTouchArray[pID]["ended"] > updateImage > end touchEnd > > on updateImage > lock screen > if panning then > put endX0 - startX0 into translateFromTranslatingX > put endY0 - startY0 into translateFromTranslatingY > put currentOffsetX + translateFromTranslatingX into newOffsetX > put currentOffsetY + translateFromTranslatingY into newOffsetY > else if zooming then > -- Calculate current distance between points to get new-to-old > -- pinch ratio and calc width and height > put sqrt((endX1-endX0)^2 + (endY1-endY0)^2) \ > into endDistanceBetweenFingers > put endDistanceBetweenFingers/startDistanceBetweenFingers \ > into pinchRatio > put pinchRatio * currentContinuousZoom into newContinuousZoom > put imgWidth * newContinuousZoom into newWidth > put imgHeight * newContinuousZoom into newHeight > > -- Get the point between the two touches, relative to upper-left > -- corner of image > put ((endX0 + endX1) / 2.0) into centerPointEndX > put ((endY0 + endY1) / 2.0) into centerPointEndY > > -- This is the translation due to pinch-zooming > put (currentWidth - newWidth) * percentageOfImageAtPinchPointX \ > into translateFromZoomingX > put (currentHeight - newHeight) * percentageOfImageAtPinchPointY \ > into translateFromZoomingY > > -- And this is the translation due to translation of the > -- centerpoint between the two fingers > put centerPointEndX - centerPointStartX into \ > translateFromTranslatingX > put centerPointEndY - centerPointStartY into \ > translateFromTranslatingY > > -- Total translation is from two components: > -- (1) changing height and width from zooming and > -- (2) from the two fingers translating in unity > put translateFromZoomingX + translateFromTranslatingX \ > into translateTotalX > put translateFromZoomingY + translateFromTranslatingY \ > into translateTotalY > > -- the new offset is the old/current one plus the total > -- translation component > put currentOffsetX + translateTotalX into newOffsetX > put currentOffsetY + translateTotalY into newOffsetY > > -- Set the image attributes on the card > set the width of sZoomObj to newWidth > set the height of sZoomObj to newHeight > end if > set the left of sZoomObj to newOffsetX > set the top of sZoomObj to newOffsetY > > -- clear touch array for ended touches after updating > repeat for each key tKey in sTouchArray > if sTouchArray[tKey]["ended"] then > if tKey is sTouch0 then > put sTouch1 into sTouch0 > put endX1 into endX0 > put endY1 into endY0 > end if > if panning or zooming then > put newOffsetX into currentOffsetX > put newOffsetY into currentOffsetY > end if > if zooming then > put newWidth into currentWidth > put newHeight into currentHeight > put newContinuousZoom into currentContinuousZoom > put endX0 into startX0 > put endY0 into startY0 > end if > delete variable sTouchArray[tKey] > end if > end repeat > updatePanZoomState > unlock screen > end updateImage > > on updatePanZoomState > put false into panning > put false into zooming > if the number of lines of the keys of sTouchArray is 1 then > put true into panning > else if the number of lines of the keys of sTouchArray is 2 then > put true into zooming > end if > end updatePanZoomState > > > > > _______________________________________________ > use-livecode mailing list > use-livecode@lists.runrev.com > Please visit this url to subscribe, unsubscribe and manage your > subscription preferences: > http://lists.runrev.com/mailman/listinfo/use-livecode > _______________________________________________ use-livecode mailing list use-livecode@lists.runrev.com Please visit this url to subscribe, unsubscribe and manage your subscription preferences: http://lists.runrev.com/mailman/listinfo/use-livecode
