Building a geometry in Matlab

hi how are you
I have a microwave complexe geometry or I find it complexe, a parallalpepide with several holes inside it, well I must analyse it using matlab, my problem is How to build such geometry using matlab, I read that a complexe geometry should create in approporiete software (Adobe Photoshope or Blender) and exporte it as STL-file to matlab, actually, I try this way but in my analyse work all sizes must change in every iteration (diameters of holes, length, width and hight of parallalpepide), so do you mind to give me some Matlab functions allow me to design my strucutre and if you can some useful tutorials about this subject.... thank you very much for any idea