This tool allows you to insert an image into the Graphics View.
Then, specify the desired location of the image in one of the following two ways:
- Click in the Graphics View to specify the position of the image’s lower left corner.
- Click on a point to specify this point as the lower left corner of the image.
Then, a file-open dialog appears that allows you to select the image file from the files saved on your computer.
- In the GeoGebra Desktop Version you can use the keyboard shortcut Alt-click, after selecting the tool Image, in order to paste an image directly from your computer’s clipboard into the Graphics View.
- Transparent GIF and PNG files are supported, but for PNGs you may need to edit them first so that they have an alpha channel (for example using IrfanView, save using the PNGOUT plugin and choose RGB+Alpha)
- Inserted images will be auxiliary objects by default.
Properties of Images
The position of an image may be absolute on screen or relative to the coordinate system. You can specify this on tab Basic of the Properties Dialog of the image.
You may specify up to three corner points of the image on tab Position of the Properties Dialog. This gives you the flexibility to scale, rotate, and even distort images (see also Corner command).
- Corner 1: position of the lower left corner of the image
- Corner 2: position of the lower right corner of the image
- Note: This corner may only be set if Corner 1 was set before. It controls the width of the image.
- Corner 4: position of the upper left corner of the image
- Note: This corner may only be set if Corner 1 was set before. It controls the height of the image.
- Set point A as the first and point B as the second corner of your image. By dragging points A and B in Move mode you can change the width of the image.
- Now, remove point B as the second corner of the image. Set point A as the first and point C as the fourth corner and explore how dragging the points now influences the height of the image.
- Finally, you may set all three corner points and see how dragging the points distorts your image.
- Set Corner 1 to A
- Set Corner 2 to A + (3, 0)
- Set Corner 4 to A + (0, 4)
- Note: If you now drag point A in Move mode, the size of your image does not change.
You may specify an image as a Background image on tab Basic of the Properties Dialog. A background image lies behind the coordinate axes and cannot be selected with the mouse any more.
- Note: In order to change the background setting of an image, you may open the Properties Dialog by selecting Object Properties from the Edit Menu.
The Transparency of an image can be changed in order to see objects or axes that lie behind the image. You can set the transparency of an image by specifying a Filling value between 0 % and 100 % on tab Style of the Properties Dialog.