fixed makefile for render_to_png example
fixed makefile for render_to_png example

JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,JianpingCAI/libigl,aaronzou/Shape-Deformation,JianpingCAI/libigl,JianpingCAI/libigl,JianpingCAI/libigl,aaronzou/Shape-Deformation,aaronzou/Shape-Deformation,aaronzou/Shape-Deformation