So, let's continue to dissect these nice presentation templates from our Indonesian community. Download the same template as in previous article. Open it in LibreOffice Impress and look at first slide:
Try click somewhere on slide in area with rectangles. You can select any from these rectangles include the largest grey rectangle that author used as background for all composition. Its all are just shapes! This is an absolutely wrong way when you create a presentation template!
First, user shouldn't have an opportunity to select any slide background elements. This will interfere with and distract him from creating the presentation. User should understand clear that he can change only heading text on first slide of his future presentation.
And second problem with these many shapes is its size. Every shape is an different object with own parameters, like position on page/slide, z-order, weight and height, area color/gradient, etc. and therefore every shape has a not small size.
The best way here is to create a background for your slide in another graphic software, like LibreOffice Draw in our case (or GIMP or Inkscape). Note, your image should have the same size as your future presentation template, like 16:9 or 4:3, or A4. Then save that image as PNG with the best quality somewhere on your PC.
A next step is to set up your image as background for a slide. There are several methods for it. Simpliest method is follow: open a Properties section in Sidebar. Press a "Insert image" button. Find and select your image in "Set background image" dialog and press "Open" button there. Voila! You have a slide background (I used another image and I before deleted all these shapes just for visibility):