The size of the mobile terminal, is substantially independent of the density of the unit DP, i.e. logical resolution, mainly to facilitate different sizes above, show the same effect.
Physical Resolution: px
Density factor: density generally indicates how many pixels per inch. 160 is a reference parameter, the density / density factor obtained 160, generally 0.75,1,1.5,2.
Logical resolution: physical resolution / density factor
In iphone6 an example, the physical resolution of 1334 * 750; 320 pixel density value, the density factor is 2; logical resolution is 375 * 667
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