Many pictures Have been cut from polygons, but doing so did not set a transparent background color and appears annoying black. Or in other cases, we want a range of colors not to be visible; Let's see how to do it:
With gvSIG.
I'm using The stable 1.9 version, that finally the download madness ended, and in less than twenty minutes it goes down. By the way, see the locator in the left panel, in the style of Qgis.
To add transparency to the image the following is done:
- Right click on the layer, in the side frame, we choose Raster properties.
- Then in the displayed panel, we choose the tab transparency, And activated the checkbox
- It is necessary to know the rgb color combinations, in this case I want to remove the black, the combination is easy: 0,0,0. So we add it, at the moment the black becomes transparent.
- In case you do not know the rgb code, you can select it from the screen with some free programs that go around, like the Visual Color Picker, to give an example.
To save the changes press to accept
More colors can be added, although it would not hurt that for future versions gvSIG will add a color selector that captures it with a click on the screen.
With Microstation V8
At Raster manager, Select the image with the right button, and then Attachment settings.
- We checked the checkbox Transparent
- Then we choose the color that is expected transparent.
- Then press the button Apply
Oops! You can only choose one and a transparency condition for all the rest.
