What technique is used to represent the true shape and size of a building?

The technique used to represent the true shape and size of a building is orthographic projection. This method involves multiple views of the object, typically including a plan view (top-down view) and elevation views (front, side, or rear views), which are all drawn to scale. Orthographic projections maintain the true proportions and dimensions of the building, allowing for accurate representations that can be used for construction and design planning.

In contrast, aerial views provide a perspective from above but may not accurately show the dimensions due to foreshortening or distortion. Perspective drawing conveys depth and three-dimensionality, making objects appear more realistic, but compromises the true scale and shape for the sake of visual impact. Oblique projection offers a way of depicting a three-dimensional object on a two-dimensional surface, yet it does not maintain true proportions and can lead to misunderstandings of the object's actual dimensions. Thus, orthographic projection is the most reliable method for clearly displaying the true shape and size of a building.