Hello, I think, that is bug. When my red heart fill black heart (background), it is done in 64% instead of 100%, why? And how fix that? PS: I am using progress bar.
Hello Renzotom,
Your issue could be caused by your tiling setting that you have for your image, the settings associated with them can cause a progress bar to look complete when in fact it’s starting the tile for the next bar.
I set in my background and fill image NO TILLING, but there is still problem, but now there is 66% instead of 64%.
I am tried add new progress bar and only change background and fill image to the heart. It looks like that:
But… here is also problem, it is complete when reach 60%.
Your issue may be in how you are laying the image & size. I was unable to reproduce your issue. However, I did get a heart to successfully change fully from one color to another.
Firstly I made 2 images based on the same Heart to ensure they were the same size (Screenshot_01 & Screenshot_02)
Next, I Created a new Widget Blueprint and added a progress bar as a child of the canvas Panel (Screenshot_03)
Next, I imported both heart images into my project and opened the details for my Progress bar
After that, I set the Background Image as the Empty Heart. I set its image size to 128 for both X and Y, set Draw as to Image, and set tiling to No Tile
Next, I set the Fill Image as the Pink Heart. I set its image size to 128 for both X and Y set Draw as to Image, and set tiling to No Tile.
Next, I set the Percentage to 0 and set the Bar fill type to Bottom to Top
(Screenshot_04)
Next, I changed the Percentage around to make sure the images lined up. And with the following set of the Heart should transition fully from One color to the other without issue.
Maybe it is beacuse my Heart made in Blender isn´t too big (or isn´t too good on camera)? You can see there I have too many space around (but I am tried make it via camera better, but it is too hard 
.
See, I tried it how you do it and still nothing.
I think, that Heart is bad, but I don´t know, how do it in Blender 
I am found method, how import correct Heart, thank you for good answer. And can you look to my other questions please?
Blender is generally used as a 3D asset creation program, and may not be the best choice for creating 2D elements. There are many free 2D drawing programs out there that may be better for creating the asset you need!
I know, but when I create 3D object (ex. pickable heart), I want same heart for HUD, so I simple render 2D image from that 3D object, when I must make new in another 2D drawing program, it will be more time-consuming.