SKETCHPADThe World’s First (And Largest) Tablet PCBackgroundSketchpad was created as a PhD thesis project by Ivan Sutherland in 1963, a man now considered one of the forefathers of computer graphics, helping pave the way for a slew of graphics software and hardware for generations to come. It is generally considered a pre-cursor to the next great leap in graphics: Computer Aided Design (CAD). FeaturesBet you didn’t know that a computer the size of a warehouse and a relatively small CRT monitor were the bare-bones behind Sketchpad. This baby would actually draw a simple geometric shape and then implore the user to “draw” by manipulating the original shape along with adding additionalcomponents to it, thus making the starting simple geometry more complex. It could detect other geometric objects and snap points and tangents together. Not only that, Sketchpad could copy and ZOOM, something which was incredibly revolutionary. And let’s not forget that wonderful light stylus, a concept which is still being studied to this day. To call Sketchpad merely a precursor to the modern day Tablet is to underestimate it. Since the graphics produced by Sketchpad were mathematical and resolution-independent, it would not be considered incorrect to label it the world’s first free-form vector graphics tool.SKETCHPADThe World’s First (And Largest) Tablet PCThe StylusThe computer would establish tracking of the pen by having a person orient it through the use of crosshairs which the computer would prompt for a person to touch with the pen. The pen worked as a coordinate input device through the use of optics, and was chosen as the primary input device based on the goal Sutherland had of creating a more free-form, unconstrained art experience with a computer. It should be noted that the computer was extremely sensitive to the position of the light pen, and frequently needed to re-establish tracking. When the pen wasn’t perfectly on top of a desired target, the position would be interpolated, referred to in the reading as the pen’s “pseudo location.” Drawing was ended by having the user flick their pen swiftly to the side, thus causing the tracker to lose the signal. It is interesting to note that the Quantel Paintbox systems used today use this exact same technique when one wishes to pause or stop “drawing” in order to pull up menus or shut down the system.Today’s typical passive Tablet works by using electromagnetic signals instead of optics, in which the tablet broadcasts a signal that is picked up by an LC circuit in the stylus. These passive tablets move the cursor by floating the tip of the stylus above the tablet (same as moving the mouse, only elevated off the surface). To initiate an action (the equivalent of a click), you simply the tap the stylus on the tablet. This changes the properties of the LC circuit, unleashing a new signal which is converted into a digital stream of information by the tablet driver and sent to the computer.SKETCHPADThe World’s First (And Largest) Tablet PCSome Functions: Using Newly Developed Object Oriented ProgrammingDeleting – There was no ‘Undo’ in Sketchpad, so you had to be careful when you drew. As the reading put it, “…removal of certain picture parts will remove other picture parts in order to maintain consistency.”Merging – You could merge basic shapes. Just as today, two independent items that were merged became one object (duh), thus meaning objects that were dependent on only one of the merged items now became dependent on the whole merged object.Instancing – Basically copying under a master object. You would manipulate the original, and the copies would manipulate in the exact same fashion.Copying – Treated more like a mirror-function in Sketchpad than the copy command we all know and love today, an exact replica of the master object was created, but unlike instancing, if you manipulate the master object, the newly copied item won’t be impacted. Zooming – Done with the help of a couple knobs, amazingly the computer could zoom in up to 2000x, although how that helps when you’re dealing with simple solid, mathematically-stringent lines wasn’t established.THENTHENNOWQuantel PaintboxLiterally the modern day version of Sketchpad. It does not have an operating system in the conventional sense, rather the hardware itself actually produces graphics. The Quantel system is quite a bit in broadcast journalism, and is also a heavily favored graphics platform in Europe, particularly in England.NOWTablets and Tablet PC’sTablets work with (or in some cases are) PC, Macs, etc. but unlike Quantels, they require an OS to run and are to be used in conjunction with graphics-producing software or note taking software.Jac’s Tablet!NOWSIGGRAPH
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