paint objects - all you ever wanted to know

There are various ways of getting a graphic image into ToolBook and using a Paint Object is just one of them. A Paint Object is a Graphic which contains a Raster image - that is, an image composed of pixel data - commonly thought of as a bitmap image. When you add such an image to your page, the image is stored on the page itself, or the background if that is where you put it.

INSERTING A PAINT OBJECT:
Using the Insert Menu, you can insert a graphic onto the current page or background. The graphic that you insert has to be a graphic that is stored on your computer as a file.

ToolBook has built in filters to recognize most available image file types, such a BMP, GIF, JPG, TIF, WMF, etc. Some image formats, such as BMP and DIB will come into ToolBook during this import process as a Paint Object, and others such as GIF, JPG and TIF will import as Picture Objects.

Note: If you have a 500k image that is stored in a tightly compressed 20k JPG file, when you import the image into ToolBook, the size of your TBK file will increase by the full 500k. ToolBook does not store imported images internally in their native format, but rather stores them as a fully decompressed bitmap.

PASTING IN A PAINT OBJECT:
If you are using an image editing program such a Paint, PhotoShop or Paint Shop Pro you may also find it convenient to simply copy and paste your edited images directly from the image editing software.

To ensure your copied image is pasted into ToolBook as a Paint object, use Paste Special from the Edit menu rather than simply using Paste. This way you can specifically choose to paste a Bitmap version of your clipboard image into ToolBook.

Note: By default, if you simply use Paste instead of Paste Special, ToolBook will default to pasting in a Picture Object rather than a Paint Object (bitmap) if it can find a Picture Object in the clipboard.

IDENTIFYING A PAINT OBJECT:
Once you have a Paint Object on your page, you can tell for sure that it is in fact a Paint Object by right-clicking on the image. The right-click menu will reveal the type of object.

LIMITATIONS OF A PAINT OBJECT:
You will quickly notice that you can't resize Paint Objects. The figure below shows an original paint object (framed in red) and an attempt to make is smaller and also an attempt to make it bigger - both which don't provide the effect you were probably hoping for.

FEATURES OF A PAINT OBJECT:
If your Paint Object is surrounded by a solid color, like the sheep in my example which is surrounded by solid white, you can instruct ToolBook to make that white area transparent so you can see through the white and see what is underneath it.

Using the Properties for Paint Object settings you can turn on the Chromakey feature and then define the transparency color [the fill color] - in my case the color is white. My figure below shows one sheep configured to use this effect and one sheep not configured.

If the color you want to be transparent is in fact white, you also have a secondary way of making the White transparent. Simply turn on the Transparency setting and don't bother setting the Chromakey feature. This only works if the color you want made transparent is in fact white.

CONSIDERATIONS WHEN EXPORTING FOR DHTML:
When you export your ToolBook file to DHTML, Paint Objects will be converted to either a GIF or JPG file based on the following criteria.

• If the Paint Object has a Chromakey value set, the image will be exported as a GIF image.
  

• If no Chromakey is set, the image will be exported as JPG.

The basic reason for this is that a JPG does not support a transparency (chromakey) feature, but the GIF format does.

Why is this important to know? Because the quality of your images could be affected.

• GIF images only hold a maximum of 256 colors. If your image was complex enough to need more than 256 colors and you specified a Chromakey setting, the image will have to be exported as a GIF, and this could result in color shade shifts or a dithering effect which makes your image appear grainy.
  

• JPG images hold 16 million colors, and therefore is able to represent virtually any image well, however the compression scheme that the JPG file format uses can result in some visual distortion - often referred to as JPG artifacts.

Quirky Exception: Lastly be aware that although you can get your Paint Object to appear transparent by simply enabling the Transparency setting, and not bothering to enable the Chromakey setting, you will find that the export process will not honor that form of Transparency. You will actually end up with a GIF image but unfortunately the Chromakey value will not be configured within the .GIF file and therefore in the Browser it will not appear as transparent. The bottom line here is that if you want to get your transparency working in DHTML for Paint Objects, you MUST use the Chromakey setting, and not the Transparency setting.