ARM Club 1/ARM_CLUB_CD.iso/contents/comdemos/progs/imagery/!TinyImage/Tutorial

Text File | 1992-07-11 | 10.9 KB | 193 lines

Imagery Tutorial - John Whigham - 11/06/92
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Introduction
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This section of the manual provides you with a blow-by-blow account of the
creation of a picture using Imagery. It is hoped that this may give you some
idea of what can be achieved and may make your first attempts as using the
package somewhat easier.

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The first thing you might like to decide upon when about to embark upon your
first masterpiece is what exactly it is that you are going to draw. Some
people like to just start and see what developes from there but, lacking any
real artistic flair, I decided to look about for inspiration and soon found
a nice airbrushed painting of a jukebox.

One nice feature that the jukebox possesed was that it was largely
symmetrical, which meant that I could draw just one half of it, which I
could then mirror across to make up the other half, therefor saving myself
both some time and effort.

Having my inspiration and software handy, it was time to put pen to paper,
or at least mouse to mousemat. The first thing I did was to use the "SET
FRAME" feature from the "SPECIAL" menu to create a frame the same height as
the picture but just half the width, I then placed this so its left edge lay
along the leftmost edge of the picture, this then gave me a line down the
screen exactly half way accross the picture. I needed this so that I could
draw whatever I liked on one side, the left say, and then mirror it onto the
right side where it would fit perfectly, leaving the finished picture
central on the screen.

Next came a basic outline of the jukebox, scene (1) shows what I came up
with, I used the "WIRE ARC" shapes function to draw the curves for the top
while the "RUBBER LINE" paint option was used to draw most of the other
lines. The "PIXELS" paint option, when used in conjunction with the "ZOOM"
facility, is useful for tidying up stray lines and pixels.

Scenes (2), (3) and (4) show more detail being added to this basic outline.
Again, most of this work was done with the "RUBBER LINE" function although
such features as "SKETCH", "WIRE RECTANGLE" and "WIRE ARC" were also used at
times. Remember that all the painting functions operate in conjunction with
the "ZOOM" feature so for fine detail, working at a magnification of 2 or 4
times may help.

Scene (5) shows the interior of the top section shaded. This would be quite
tricky and time consuming if we were working with paints and brushes, but
the beauty of computer art is that often the computer can be made to do the
hard work for you, this is one such case. I started by filling the area
using the "PATTERN FILL" function which can be found via the "FILL" submenu
of the "PAINT" menu structure. I selected the triangle pattern for the
simple reason that I liked the look of it. Once the area was filled with
this pattern, which is made up of two colours, I defined two graduated fills
using the "GRADUATED FILLS" editor accessed via the "EDIT" menu structure.
One fill used only two shades of red while the other was a graduation from
orange to red using eight shades. I made all the colours transparent with
the "SET TRANSPARENTS" paint option then made one of the two colours used in
the triangle pattern solid again. An area graduated fill over this area with
the red fill defined earlier then gave this one colour a nice red shade. The
other colour used in the pattern was then made solid and the first
transparent again. A second area fill with the orange-red fill completed the
effect shown in the scene.

Next I decided to fill some of the other areas using the graduated fill
function. This function is very useful for people such as myself who are not
overly blessed with artistis talent as it allows quite proffesional results
to be obtained quickly and with relativly little fuss. One method which I
found useful for filling areas where the area to be filled is broken up by
other parts of the picture is to use the flood fill on the areas to be
filled with an unused colour and then to make all bar this colour
transparent. A graduated area fill can then be used enclosing all the
sections of the area which will ensure an even colour graduation over all
the areas. This trick can also be quite useful when using a graduated flood
fill, if you fill the area with plain colour first, it can help to see just
where exactly the graduated fill is going to cover.

Scene (6) shows some of the area of the jukebox filled with plain colour,
ready for the graduated fill. One point to note here is that I filled in
some of the white outlines with the colours before using the graduated fill,
otherwise all my nice colours would be bounded by white lines - not exactly
what I was looking for. Scene (7) shows some of the flat colours replaced
with graduated fills, a definite improvement I think.

Next came some more fills with both graduated and flood fills, as shown in
scene (8). Again it was important to remove the white lines from around the
swirly patterns on the front pannel of the jukebox, some use was made of the
"COLOUR REPLACE" function from the "SPECIAL" menu here to replace the white
pixels with the green I was using to fill the patterns.

The patterns were filled using a similar process to that described above for
the interior of the top section. An area fill had to be used because the
patterns did not connect, all bar the green colour were made transparent to
achieve this. The triangle pattern fill was used again followed by a pair of
graduated fills - one for each pattern colour as shown above. Scene (9)
shows the final effect.

Scenes (10) upto (17) show how the picture progressed from there. Most of
the work was just using graduated and flood fills to fill in the areas
originally drawn as white outlines. The stack of records were initially
drawn as a stack of alternating grey and black lines with the bottom one
being a little thicked to form the turntable. The grey lines were then
filled using a horizontal graduated fill which was made up of sixteen
varying shades of grey and white to create the effect shown.

Scene (17) shows the finished jukebox, or rather half of it. The picture
still only shows the left half of the jukebox so I thought it was about time
to see about filling that blank right hand side of the picture. This was
achieved using the "COPY AREA" function provided by the "MANIPULATE" menu
structure. The left side of the jukebox was selected then the "X FLIP"
option was selected from the area control dialogue box before pasting the,
now mirrored, half jukebox onto the right hand edge of the half that was
already there, hey presto - one complete jukebox!

A few minor touches finished off the jukebox itself but, not withstanding
any lack of talent, I decided to create a scene for my musical masterpiece.
First I decided to export the entire jukebox as a sprite with a mask to
replace the black background. This would let me paste it straight into
whatever scene I came up with. The problem was that I could not just make
the background black transparent as black was also used within the jukebox
itself and these bits would also go transparent when exported. The answer
was to draw round the jukebox using an unused colour, in this case a bright
pink, and the "PIXEL" function. The picture was magnified eight times to
make this easier. Once I had an outline, I could flood fill the background
with the same pink colour which I could then make transparent for the
exporting. The "EXPORT" function from the "FILE" menu was selected next and
the entire jukebox selected with the "MASK" option of the area control
dialogue box on to make sure a mask was generated from the transparent pink
colour.

I could now start work on the background for my jukebox. I decided to do
something a little different with this and so opted for a somewhat sureal
scene of the jukebox rising out of some rippling watter. Scene (19) shows
the basic background for the scene. I started by drawing the rocks about
halfway up the screen. These were created by drawing their outlines using a
dark grey colour and the "RUBBER LINE" function. They were then filled with
a plain flood fill before using the "PIXELS", "SKETCH" and "AIRBRUSH"
functions to add the surace details. The silver tree was drawn in the same
way with a small "PAINTBRUSH" being used for the leaves.

I then used the "RUBBER LINE" function again to draw an outline of mountains
in the background aswell as the gnarled tree silhouetes. The area above this
outline was then flood filled with white to give the scene shown in scene
(19).

One graduated area fill later and I had scene (20) with a nice blue dawn
sky. I wanted to put a planet of some sort against the left hand side of the
sky and toyed with the idea of putting a shaded sphere there to represent it
but then decided against this, it would be simple to do but would not look
all that much like a planet. Instead I used a small program that I had to
generate a gas-planet type effect on a circle, I saved the output from the
program as a sprite with a mask to cover the black background and then
simply dragged this onto the picture to give the scene in scene(21).

For the water effect, I copied everything from the rocks upwards using the
"COPY AREA" manipulation function with the "X FLIP" option set to invert the
image before plotting it inplace of the black area at the bottom of the
picture. I wanted to give the effect of the jukebox being about half
submerged in the water so I went back to my jukebox sprite I exported
earlier and used paint to remove the bottom half of the sprite.

This edited sprite was then dragged back onto the picture and plotted at
half height and inverted to create the proposed reflection of the jukebox in
the water. Scene (22) shows the image as it then stood.

The water did not look very realistic, reflections in water are not usually
as bright as the original and are rarely perfectly flat. To address the
first problem, I selected a light blue colour and used the "TINT AREA"
function from the "SPECIAL" menu to give the water a more blue hue, as shown
in scene(23). The colour now looked about right but the reflections were
still perfectly flat. To the rescue came the "WOBBLE" function from the
"MANIPULATE" menu. This function can be a little tricky to control exactly
what effect will be created but with a little experimentation and repeated
use of the "SHOW" option, I managed to come up with quite a good ripple
function - as shown in scene(25). This function was applied to the entire
water area to create quite a pleasant looking water effect.

To complete the picture, all that was required was to import the sprite
containing the top half of the jukebox again and plot it to line up with the
reflection plotted earlier. Scene(24) shows the final picture, tentativly
titled "Coin-op Water Music"!

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We hope that this walkthrough of the creation of a picture has given you
some ideas of what can be achieved using just a few of the facilities
provided by Imagery and has shown you that you don't need to be an artistic
genius to create quite pleasing results quickly and easily.

Good Luck!