Shader Working on Simulator and Playground But Not on Device

Solar2D Custom Shader Effects
1

Hi

I created a shader which works fine on the simulator and on the playground but not working on device. It shows the gradient background but not the stars…

Tested on a Samsung Galaxy S5 and Galaxy Mega.

Anybody know what the problem could be ?

Link to the shader on playground.

https://goo.gl/kcYiBh

2

It’s possible if this is a high precision shader your device may not support it. Use this call:

local supportHPS = system.getInfo( "gpuSupportsHighPrecisionFragmentShaders" )

to see if your device supports your shader.

3

Hi.

As Rob says, you’re probably low on precision. If so, then those 415 values are probably getting snapped to 256 and you’ll never get a fraction, much less two that sum to .97 or more.

Try something like

P\_UV float Hash(P\_UV float n) { #ifdef GL\_FRAGMENT\_PRECISION\_HIGH return fract( (1.0 + cos(n)) \* 415.92653); #else return fract( (1.0 + cos(n)) \* 41.592653); // or 4.1592563... #endif }

in the hash function.

You might need similar adjustments to threshold. (If everything’s a number < 1 you’ll have quite a lot of precision, actually.)

4

Thanks. I’ll try that when I get a chance and post the feedback…

5

It’s possible if this is a high precision shader your device may not support it. Use this call:

local supportHPS = system.getInfo( "gpuSupportsHighPrecisionFragmentShaders" )

to see if your device supports your shader.

6

Hi.

As Rob says, you’re probably low on precision. If so, then those 415 values are probably getting snapped to 256 and you’ll never get a fraction, much less two that sum to .97 or more.

Try something like

P\_UV float Hash(P\_UV float n) { #ifdef GL\_FRAGMENT\_PRECISION\_HIGH return fract( (1.0 + cos(n)) \* 415.92653); #else return fract( (1.0 + cos(n)) \* 41.592653); // or 4.1592563... #endif }

in the hash function.

You might need similar adjustments to threshold. (If everything’s a number < 1 you’ll have quite a lot of precision, actually.)

7

Thanks. I’ll try that when I get a chance and post the feedback…