Photoshop uses PX as a unit of measure for the forms and in development the app uses DP, I know how the conversion works From PX to DP
The conversion will depend on how the original design in Photoshop was constructed. Android’s dp
units are density independent pixels. 1dp might render as 1 screen pixel, or 2, or 3, or 4, or some other value, depending on the device and Android settings.
Here’s a list of the common conversions:
- 1 dp = 1 pixel, or 1×, for
mdpi
displays (~160PPI).
- 1 dp = 1.5 pixels, or 1.5×, for
hdpi
displays (~240PPI).
- 1 dp = 2 pixels, or 2×, for
xhdpi
displays (~320PPI).
- 1 dp = 3 pixels, or 3×, for
xxhdpi
displays (~480PPI).
- 1 dp = 4 pixels, or 4×, for
xxxhdpi
displays (~640PPI).
So, the big question is which density do you want to build your mockups in? You can choose any of the above densities. Your choice will dictate the conversion, and other factors.
My preference is to design at 1×, a scale where 1 dp
= 1 px
= 1 CSS px
= 1 iOS point
. That will mean your mockups are lower resolution than the device itself, but it means the conversion requires no change to the value.
When you’re done, Photoshop has a few ways to export assets for the various densities. Export As
and Generator
can build the other scales, or you can use Save for Web
and slices (like I do).
Here’s Photoshop’s Export As window, with the exporting set up for 1×, 2× and 3× densities (for iOS, in this case).
