@Override
    public void onDraw() {
        GLES20.glUniform1f(getHandle("brightness"), brightness);
    }
brightness value ranges from -1.0 to 1.0, with 0.0 as the normal level
dkplayer-sample/src/main/java/xyz/doikki/dkplayer/widget/render/gl2/filter/GlBrightnessFilter.java