The Gradient Experience / Progressbar

[Lolonois]

I like the progressbar showing up by default since early March on the ES dev builds.

However, first I noticed the color did not match to the ES logo, then I thought it should have an diagonal graidient (gradient to right / to bottom is implemented already) like the ES logo has an drop shadow from light top-right.

The current implementation works for left-to right and top-to-bottom gradients, although it uses a strange variable name horizontalGradient, strange because given the different orientations a physical monitor can have in a cabinet/cocktail arcade horizontal (the flag) is not nescessary horizontal (orientation): https://en.wikipedia.org/wiki/Vertical_and_horizontal#/media/File:Mystery_of_the_horizontal_y-axis.PNG

I propose some additional gradient orientations and stringent names (using top-bottom and left-right instead of "horizontal"/"vertical" ("vertical" means horizontalGradient = false). I use quotes since the real orientation depends on how the monitor is placed in a housing, as noted above.

Anyhow, enough text, see by yourself (sample colors to emphasis the gradient orientation, red is color blue is colorEnd):

Gradient NONE:

Gradient TO_BOTTOM:

Gradient TO_RIGHT:

Gradient DEFAULT: colorEnd at bottom-right

Gradient FLIP_LR:

Gradient FLIP_TOPBTM:

Gradient FLIP_TOPBTM and FLIP_LR:

The final result would look like this with the darkest Turquoise color the the brightest Turquoise color of the ES logo:

The PR keeps backward compability with the horizontalGradient and its effect. The diagonal gradients could also be used by themes for rectangle areas if new theme XML elements will be defined and evaluated by ES.

https://github.com/RetroPie/EmulationStation/pull/744

[madmodder123]

awesome