Blending rasterized images
You can blend the stroke and fill values of the selected rasterized objects or bitmap images with the stroke and fill values of background objects present on the same layer. The Plazmic® Composer calculates the fill and stroke values of the overlapping portions of the selected objects and the background objects based on the blending method you choose. To apply a blending method, you must rasterize an object.
The Plazmic Composer calculates the blended color values by combining the values of the red, green, and blue (RGB) color channels for each pixel where the rasterized image and the underlying object(s) overlap. For example, suppose you create and rasterize a rectangle with a fill value of RGB 127, 0, 0 (dark red) that overlaps another rectangle with a fill value of RGB 127, 127, 0 (olive green). By applying the Subtract blending method to the dark red rectangle, the RGB values of the overlapping section change to RGB 0, 0, 0 (black). If you apply the Add method, the RGB values of the overlapping section will be RGB 255, 127, 0 (orange).
The Plazmic Composer actually calculates these RGB values using the range 0 to 1 rather than 0 to 255. The only method where this makes a difference is the Multiply method. Using the same example, the dark red rectangle would have RGB values of 0.5, 0, 0, and the olive green rectangle 0.5, 0.5, 0. Multiply those three sets of values together and the result is 0.25, 0, 0, which is equivalent to 63, 0, 0 (darker red).
You can apply one of the following blending methods to any rasterized object or bitmap image:
Blending method |
Effect |
Example |
|---|---|---|
Normal |
None (no blending method applied). |
|
Multiply |
The RGB values of the object and the underlying object(s) are multiplied together for each of the three channels. |
|
Screen |
The selected object “burns through” underlying objects. This has no effect on the background color. |
|
Erase |
The selected object is removed from the canvas. If an object is underneath the bitmap object, the shape of the bitmap object might create the effect of a “cut-out” on the underlying object. |
|
Add |
The RGB values of the object and underlying object(s) are added for each of the three channels. |
|
Subtract |
The RGB values of the underlying object(s) are subtracted from the object’s values for each of the three channels. |
|
Darkest |
The lower of the two RGB values is used for each of the three channels. |
|
Lightest |
The higher of the two RGB values is used for each of the three channels. |
|
Difference |
The difference between the object’s and the underlying object(s) RGB values is used for each of the three channels. |
|
Average |
The average of the object’s and the underlying object(s) RGB values is used for each of the three channels. |
|
Invert |
The object’s alpha level is used to invert the underlying objects. |
|
Dissolve |
A random pattern is created based on the opacity of each pixel. Tip: When using the Dissolve blending method, you must set the opacity level of the object to see the effect. |
|
Replace Hue |
The hue of the object is used on the underlying object(s). |
|
Replace Saturation |
The saturation of the object is used on the underlying object(s). |
|
Replace Luminosity |
The luminosity of the object is used on the underlying object(s). |
|
Replace Color |
The hue and saturation of the object is used on the underlying object(s). |
|
XOR Mask |
The difference of the object opacities is computed, the absolute value is determined, and the dominant color displays. |
|
Alpha Mask |
This option is the inverse of an erase. The composited object shape is used to mask out all lower objects. |