This is !DrawPersp, version 1.31 (28 September 1996)
Intro
=========
This is essentially a vector program, with which you can create drawfiles.
Its special feature is that its drawing tools all provide operations, that
take into account the perspective of a scene.
Perspective
============
Perspective is caused by the fact that objects appear smaller, the further
away they are. This causes vertical, and horizontal surfaces, to scale down
smaller at greater distance, and if they were continued, would tend to
disappear, or become infinitessimally small, at an infinite distance away.
Such a place we call a 'vanishing point'.
A scene in which all buildings are laid out in a true rectangular grid, will
have two vanishing points, but normally only one will be in a visible area
of a picture at a time. When they both show a distorted effect can be
achieved.
If one vanishing point is in the centre of the picture, a drawing of a scene
looking straight down a straight road can be achieved. If it is placed off
centre an effect of looking across a road in a slanting way can be made.
Use
===
The best mode for this is 21 or 28. Other modes work but some give
poorer results.
The select button is used for most operations described below, while with
one exception adjust provides you with temporary vertical and horizontal
guides, emanating from the pointer.
The program is installed on the icon bar in the usual way, by clicking on
the icon in the directory. The drawing window is opened by clicking on this,
and a white screen, with a toolbox and a small cross in the middle can be
seen. This cross represents the visible vanishing point. Other vanishing
points are sited off the screen at infinite distances away each side.
The top icon can be selected and the vanishing point can then be resited. In
general to get a drawing that looks correct you need to keep it about two
thirds of the way up the screen. Putting it higher gives the impression of
looking from on high. Putting it low gives an ant's eye view.
The next icon down is use for rubber banding. This is used as in !Draw, and
draws in the selected colour. This operation is the only one that does not
consider perspective; any line can be drawn.
The next icon down draws vertical surfaces. Dragging will only work from top
to bottom. dragging towards the visible vanishing point, draws a surface,
that would vanish at that point. Dragging away from it draws a surface that
would vanish at the other vanishing point, off of the screen. The textures
sub menu allows you to choose, unfilled, filled, brick, weather board, or
block. Spacings of these, can be altered from this sub menu too. This option
is selected on starting the program .
The next icon is for drawing horizontal surfaces. Click and drag, to see a
surface drawn, which tends to disappear the nearer it gets to a vanishing
point. There is a bug in this, and it pays to drag from bottom left to top
right if possible. By selecting one of the options in the sub menu, you can
choose unfilled, filled or paved options. The paved one does not yet, obey
correct perspective, but looks good. The field texture is not yet
implemented.
The next icon is for dragging simple lines, that go towards or away from
vanishing points. This probably won't often be useful, as all lines on a
picture are really more accurately described as surfaces.
The next icon is for dragging out objects that are not vertical or
horizontal. This action is used for drawing roofs. Unlike the other tools
this one has to be dragged once to do the non vertical non horizontal bit.
The next drag then creates the surface.
The next icon provides the user with a tool to plant fractal trees and
bushes at the place of the pointer. These trees can't be drawn above the
vanishing point which would be in the sky. They obey the rules of
perspective, becoming smaller further away, though their actual size, can
also be changed from their sub menu as well.
Clicking adjust on this icon opens the tree generator window that allows you
to change the type of trees in a large combination of ways. The routines are
identical to those found in another application by the same author called
!Trees. Particular types of tree can be produced from scriptfiles that can
be dragged into this window. These scriptfiles can be saved also using the
menu on this tree generator window.
The next two icons open the colour picker windows to set fill and line
colours respectively. These should open up Acorn colour pickers if they are available on the machine, otherwise they will open up an alternative picker.
Using these two picker tools is a departure from the style of !Draw, but
I feel they are more friendly than accessing them from a menu.
The selection icon is not yet working.
OLE is now working, so in a very satisfying way a click with Ctrl. held
down, loads the drawing into !Draw, if it is available. This can be used to
delete objects etc.. For those unfamiliar with OLE, a Save from !Draw, best
achieved by closing the Draw window, will ask you to save the edited file
back into !DrawPersp.
Saving
======
This can be accomplished, from the main window menu, in the
usual way. The
Drawing
=======
Users should experiment, with the above tools. Artists who
understand the rules of perspective, may find it easy, and it may be of use
to teach perspective. It is limited in several ways, by simplification, and
it really needs a fast machine, as it is written in basic, and it needs to
use a high resolution mode.
Future
======
!DrawPersp should include in the future:
More textures
More fractal options
Less bugs and more simplifications
Copyright
=========
This program is Public Domain. It may be distributed or
copied freely as long as no part of this software may is used in any other
program, whether commercial or public domain, without my prior written
consent, though any files created by this software are not bound by this
condition. This software may not be distributed for a profit, save that
