Reference images / Raster references
Raster references category in Reference images folder defines the ratios of lower resolution versions of raster references and how references are displayed when viewed from a far distance.
A full resolution version of an image is required only when the display is zoomed close to the pixel detail level. When viewing images from further away, the application can use smaller versions of the images and thus, fit more of those images in the image cache.
Lower resolution versions are not used with ECW images.
SETTING |
EFFECT |
---|---|
Medium ratio |
Sub-sampling ratio of medium resolution versions. Default is 2. |
Low ratio |
Sub-sampling ratio of low resolution versions. Default is 4. |
Thumbnail ratio |
Sub-sampling ratio of thumbnail versions. Default is 8. |
Beyond factor |
Zoom factor beyond which the raster images are no longer drawn. Default is 1000 which is a reasonable setting for ECW images. |
Draw rectangle |
If on, the application draws a rectangle using the given line color and line width for each raster image if the zoom factor is smaller than the value given in the Beyond factor field. |
Fill rectangle |
If on, the application fills the rectangle with the given color for each raster image if the zoom factor is smaller than the value given in the Beyond factor field. |