public void setGammaCorrection(boolean gammaCorrection) {
        putBoolean("GammaCorrection", gammaCorrection);
    }
Enable or disable gamma correction. If enabled, the main framebuffer will
be configured for sRGB colors, and sRGB images will be linearized.

Gamma correction requires a GPU that supports GL_ARB_framebuffer_sRGB;
otherwise this setting will be ignored.

@param gammaCorrection true to enable, false to disable (Default : true)
jme3-core/src/main/java/com/jme3/system/AppSettings.java