How to create animated images

Using ShotGraph you can create animated GIFs on-line as well as static ones. To create an animation you should use the special object called animation track. This abject is created every time you create the "shotgraph.image" object. Just after creation the animation track is empty.

To create an animation, you should do the following:

  1. Create a "shotgraph.image" object.
  2. Make the necessary drawings.
  3. Call TrackAdd function.
  4. Repeat steps 2 and 3 as many times as necessary
  5. If you want your animation to be circled, call TrackLoop function.
  6. Call TrackPlay function to get animated file or binary stream data.
The animation track use your working image size and palette are defined in the time of first calling TrackAdd.
You can not create an animated image from empty track.

Note. ShotGraph is not a specialized GIF animator. The animation features are only additional cababilities of this software. The main goal of this program is the making of static images on the fly for your WWW service.

Hint.
To get fully colorized animations with your custom graphics included with necessary colors, you can use local clipboard, instead of direct drawing the image in the main working space and sending the ready frame directly to the animation track. You can use this method if the summary color palette is too big or indefined. The necessary steps are shown below:

  1. Create the clipboard of necessary size by calling InitClipboard function. The clipboard area size should be enough to include all animation frames together.
  2. Make the clipboard working area active, by calling SelectClipboard function.
  3. Place all frames on the clipboard area.
  4. Call either WebPalette or BuildPalette method to calculate and rebuild the new image palette.
  5. Copy frame by frame from clipboard using Copy method to main working image space and sequentally add them to the animation track.
  6. Call TrackPlay method to create the animation.

Example
As example, let's join two GIF images together to create the animation. There are our two files, frame1.gif and frame2.gif. The picture size of every file is 400x50 pixels.

frame1.gif

frame2.gif
As you see, the summary palette size of both files is bigger then maximal available (256), so we will need recalculate the resulting palette on the clipboard. The script producing the animation is quite short, here it is:

set obj=CreateObject("shotgraph.image")
xsize=400
ysize=50

obj.CreateImage xsize,ysize,256
obj.InitClipboard xsize,ysize*2
obj.SelectClipboard True
obj.ReadImage "frame1.gif",pal1,0,0
obj.ReadImage "frame2.gif",pal2,0,ysize
obj.BuildPalette 0

obj.Copy 0,0,xsize,ysize,0,0,"SRCCOPY"
obj.TrackAdd -1,0,0,0,0,xsize,ysize,50
obj.Copy 0,0,xsize,ysize,0,ysize,"SRCCOPY"
obj.TrackAdd -1,0,0,0,0,xsize,ysize,50

obj.TrackLoop 0
obj.TrackPlay "frames12.gif"
The result of script working is the file frames12.gif: