Creating Compound Paths with Expression Blend

There may be a time when you need to create an effect where you are looking THROUGH an item, and lining up artwork to make it look that way is difficult and unpredictable. My favorite technique to take care of this is using compound paths in order to see what is behind an item.

The following screens show an extremely basic example of how to create a usable compound path shape.

1. Draw a basic ellipse

2. Draw another ellipse on top, this one is smaller to create a thick border effect.

3. To see how the shape is now "see through" I put a yellow rectangle in the background

 4. Select both ellipses, and then go to the top menu "Object" > "Path" > "Make Compound Path"

5. This is the result, you will now see the yellow rectangle through the circle.

I also used this technique to create text where each letter can have a different gradient color or a separate blend angle. 

1. I created the text box, and then converted the text to paths. With the TextBlock or TextBox selected go to "Object" > "Path" > "Convert To Paths"

After this, the text has been converted to different path sections, however they are still a compound path (the text is a compound path to begin with so the letters look right) and need to have the compound paths "released".  

"Object" > "Path" > "Release Compound Path"

Now the text will become solid shapes, you won't see the inside of the "P" nor the inside shape of the "A"

Select both paths that make up the "P" and make those into a compound path, then select the paths that make up the "A". Doing this with all the paths selected, they will be connected and you will not be able to give them each a separate fill.

This is a lot easier than trying to draw any text or number shape to be used in a design or control.

The screenshots below show a border with a compound path and how it displays the color(s) behind it. Now, I can simply change the color of either the background or of the blue ellipse in a control, instead of changing an entire group (the border, background and the ellipse). 

This is  the "animation" using the example. When you mouseover the button, the only change is the opacity of the element in the background. The blue one is visible when normal, but opacity is zero when mouseover with the red one now having an opacity of 85%.

Link to example 
NOTE: The design work is done in the file "CompoundPath.xaml" - but the button style is defined in a resource dictionary where I copied the design over and then added the animations using the button's existing template. It is included in the downloadable file for reference. 

I have uploaded the project here. I'm going to continue to update this as I create new examples and test out new ways to design using Blend and making it easier for me to create layouts even faster. :)

Error while rendering XAML in the designer view

Error message in Visual Studio 2010

Error message shown in Blend (Note: The window in Blend is much shorter, I spliced together two screenshots to show the full error message)

Fixed the error by going through the page (or control) and deleting all of the "d:LayoutOverride" commands that were inserted while designing in Blend.

Not sure why this worked, even had the mc:Ignorable="d" in the header, but it worked.

Creating a simple control with dimension

This was the original reason a co-worker suggested I blog some of my work. It is a relatively simple design trick but he really liked it and liked the fact it was easy and didn't require a lot of reworking to get the effect.

Step 1: I created a UserControl that contained a simple shape (in this case a circle) - for this example it will use chrome style brushes. I haven't worked with solid or gradient brushes - that will be later after I figure out the Silverlight charts a bit more. (The charts are for a current assignment, but I do want to catch up on documenting what I have been able to accomplish)
The user control also has a drop shadow applied to the shape - this helps with the final artwork having the look of dimension.

The image above shows the final basic user control.

Step 2. Created a new document (UserControl) where I imported the basic control, and copied and pasted several times. Each subsequent layer reduced using the the transform tool in Blend. (This example uses the preview of Blend 5 available from Microsoft. )
This moved the position of the chrome brushes up slightly, giving the appearance they were still using the same reflection but one was above the other.

Above is a closeup of the positioning of each control layer - they all have the exact same center, but by reducing the size the chrome effect of the brushes moves up slightly. Also, the border has a different chrome style brush than the fill does. The difference is very slight but it helps with the dimensional effect.

Step 3. Layer the control to achieve the desired affect. Below shows the complete dimensional control. When using a "curved" chrome brush - it really helps the effect pop. But, that will be a separate post since I am still catching up on figuring out a bit more coding.

Not the perfect representation, but it is all XAML, and you only have to make the image once to reuse on several other controls or pages. Could also be a good button background.

I have uploaded the files here for you to play with. It includes the brushes as well.