Changing coordinate updates waveform chart?

Hi All, hope everyone is having a wonderful 4th of July.
Alright, so I am new to labview and finding my things around the simple things pretty well, but having never taken any sort of programming interest, Im a bit behind in machine logic, so I figured I would ask here.
EDIT: using labview 2009. Have Vision package
The research I am doing involves analyzing Electron Speckle Pattern Interferometry (ESPI) images and their fringes to observe fracture points/potential weaknesses in different materials and such. I have made a simple VI which allows me to draw a line on the ESPI image and output the light intensities to a waveform chart to make it easier to objectively determine the size of the plastic region (area where fracturing is most likely to occur).
What I would like is to be able to draw or set the coordinates of the line initially, then somehow be able to move it vertically -- using either simply my mouse or a numeric controller -- and have the waveform chart update in real time as i do it.
Any suggestions? Ive attatched my programs, the one called "line.vi" uses numeric input to determine the line coordinates.
Also, since i dont sem to be able to attach bitmaps, ive uploaded a sample image here http://img594.imageshack.us/img594/3566/espiimage.png I dont know why imageshack converted it to a PNG though
thanks all
Solved!
Go to Solution.
Attachments:
line.vi ‏50 KB
light intensity line.vi ‏47 KB

Hi itschad,
did you read the context help of the chart? There it is shown what datatype you need to wire to plot more than one curve on the some chart...
"This made a weird issue where once I select the line, the intensity profile keeps adding itself over and over again onto the end of the chart, so a chart that might initially have been 100 datapoints, just keeps getting longer and longer."
This is how charts work. They keep a history (that you constantly clear). You can set the size of the history buffer. If the default of 1024 points is too much for you you may decrease this to 100 - it's just a right-click away... Otherwise you should use a graph, as a graph only plots the points that are currently wired to it (it doesn't keep a history of previous values).
Best regards,
GerdW
CLAD, using 2009SP1 + LV2011SP1 + LV2014SP1 on WinXP+Win7+cRIO
Kudos are welcome
Attachments:
test horizontal shift.vi ‏48 KB

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Changing coordinate updates waveform chart?

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