osg学习（七十四）Type mismatch in arithmetic operation between ‘vec2‘ and ‘int‘

可能是手机端语法检查更严格

glsl语句是这样的，再桌面端执行没有问题，在手机端执行会提示上述错误

vec3 tmpNormal = osg_NormalMatrix*osg_Normal;
	tmpNormal = normalize(tmpNormal);
	texCoord = tmpNormal.xy/2+0.5;

改为如下则手机端不再提示错误

vec3 tmpNormal = osg_NormalMatrix*osg_Normal;
	tmpNormal = normalize(tmpNormal);
	texCoord = tmpNormal.xy/2.0+0.5;