+ (let ((default-font-height (face-attribute 'default :height))
+ (resy (/ (display-pixel-height) (/ (display-mm-height) 25.4)))
+ point-size pixel-size)
+ (setq point-size (/ (* (float default-font-height) max-height) 10)
+ pixel-size (floor (* resy (/ point-size 72.27)))
+ point-size (* (/ pixel-size resy) 72.27))
+ (face-spec-set gamegrid-face
+ `((t :height ,(floor (* point-size 10))))))))))