renderLine16_Blend(), renderLine16_Decal(), renderLine32_Blend(), renderLine32_Decal() clipLine() frand() drawRectangle() and drawLine() remove unused private fields
GLES drivers adapted, but only did make compile-tests. git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/branches/ogl-es@6038 dfc29bdd-3216-0410-991c-e03cc46cb475