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*---------------------------------------------------------------------*
* ChromaStudio-24 beta-test documentation v0.1 *
*---------------------------------------------------------------------*
1.0 Introduction
------------
Before using Chroma, it is important to know a little about the
system and why it works the way it does. This makes understanding the
numerous features a simpler task, and is ultimately less frustrating
for the user.
Chroma is designed to be capable of performing many operations
ranging from a simple image-viewer to the rendering and management of
large multi-frame animations. Rather than using unconnected pages or
windows to hold images - as many similar programs do, Chroma holds it's
data as a sort of digital videotape. This might sound a little odd, but
it makes a great deal of sense from both the user's and the machine's
point of view. Chroma makes use of this technique to allow animations
to be generated internally with great ease, making it capable of
covering almost every aspect of the field without having to use many
other products. The Morphing and distortion features are a good example
of the integrated system.
This approach to animation is discussed further in the 'VIRTUAL
VIDEO' section of this manual.
Due to the methods employed, Chroma's interface was designed with
a high-end Video recorder in mind. All of the standard functions are to
be expected (play forwards/backwards, fast-forward, re-wind, stop etc.)
but some others are less obvious. There are buttons to allow the
insertion or deletion of individual frames, a jog shuttle to control
the direction and speed of play in realtime and a play-speed slider
for adjusting the rate of play. All of these options are designed with
animation in mind, but fit the purpose of single image editing much
more closely than you might imagine. All of these options are to be
found on the video-controller at the bottom of the screen.
Drawing tools are to be found at the very top of the screen, and
are activated with the left mouse-button. The right mouse button used
in the same way will call up a configuration menu, if any options are
available for that tool. Tools are restricted to the top row only and
are temporary - they may be swapped in and out at will.
The processing studios and remaining operations can be found on
the row of icons just below the tools. These menus either replace the
tool bar with a new set of icons, or open a configuration window
depending on the situation. These icons are permanent and do not
change at any point.
The colourful bar below the video controller is the palette
selector. This holds up to 256 different colours which may be changed
at will. The video mode decides how these colours are handled, since
256 colours is by no means the upper limit - they simply act as a
temporary list of the user's favourite shades. Two boxes are to be
found outlining two different colours - one large, one small. These
show the selected foreground and background colours respectively.
The left mouse button selects the foreground colour and the right
selects the background. This is how gradient/shaded fills are defined.
Information on colour and palettes can be found in the section
labelled 'DEALING WITH COLOURS'.
The last thing to be found on the interface is the status bar,
which keeps an eye on Chroma's internals and informs the user of
peripheral information including mouse coordinates, free and used
memory, busy/idle state, box-dragging dimensions and so on. Keep an eye
on this bar, as memory is something Chroma can chew up in no time -
even with it's internal compression and defragmenting memory system it
is still very easy to run out of ram with big images or animations.
If you are using more than 4 Megs, memory should not be a problem in
all but the most extreme cases. A system with 4 Megs or less would
benefit from a virtual-memory driver such as OUTSIDE. This is certainly
not a requirement on a 4 Meg machine, but is a wonderful enhancement
and is much cheaper than buying a ram-upgrade.
Virtual memory is explained in detail in the 'MEMORY MANAGEMENT'
section of this manual.
1.10 Getting started - A short tour
------------------------------
The first thing you will meet after running the program is the
video selector. This allows the user to set up the number of colours,
the colour resolution (18/24-bit etc.), the screen resolution and the
canvas, or picture size. Which options you select will depend on
available memory, but reasonable selections are unlikely to pose a
problem. It helps to bear in mind that true-colour requires twice as
much ram per pixel as 256-colour mode. A 640*400 true-colour image
requires 512k, and that does not take into account any memory Chroma
might require to deal with such large screens - and it does require
memory. If Chroma fails to allocate enough ram at this point, you
will be asked to re-select. For the purposes of this section, we will
choose 320*200 with 256-colours. The right mouse button informs Chroma
you wish to leave this selector and enter the program.
The first thing you will notice about the interface is that you
may not draw immediately on the canvas, even although it is at least
partially visible. While the menus are present, the screen is
effectively 'write-protected' and cannot be altered. Pressing the right
mouse button on the canvas causes the menus to swap out, giving the
user access to the screen. The right mouse button will toggle the menus
on and off if pressed continually. Beyond this, the interface holds no
great mysteries and is actually very similar in operation to GEM, but
is faster and much less prone to cracking up. The exception to this
rule is that the right mouse button generally means 'go-away' and can
also be used to access the secondary function of certain icons.
To get started, click on the 'pen' icon (top left) and press the
right mouse button on the canvas. The menus will disappear and you may
draw on the screen using the left button. When you have had enough of
this, bring the menus back with a right-click and press the number '2'
on the keyboard. You will notice that the 'pen' button will pop up and
the 'line' button beside it will press in.
This is an example of how keyboard macros can give access to many
of the options available and indeed, some functions can ONLY be
accessed via the keyboard, as it would be impractical or impossible to
implement them as icons. An examle of this is 'pick colour' which
selects the colour under the mouse pointer when the 'C' key is pressed.
It is important to remember that this program is designed to be an
extension of the artist's hands and by using keys, much time can be
saved on such commonly used operations. Icons may look nice, but it is
useful to be able to guide the mouse with one hand while zooming /
panning scrolling and generally controlling things with my other. This
allows great fluidity and reduces the number of times you need to
access the menus significantly. This is also the reason the palette bar
is always available - I find it irritating to have to look for a
palette menu in the middle of touching-up a picture, especially when
colours need to be re-selected constantly. Everything within Chroma can
be reached almost immediately, and it is definitely worthwhile learning
the keys for this reason.
A full description of these special keys are offered in the
section labelled 'KEYBOARD MACROS - TAKING THE SHORTCUT'.
1.11 The Virtual Canvas.
Once you have tried out the first couple of tools, The next step
is to get familiar with what we call the 'virtual canvas'. This is the
heart of the program, and is where your picture or 'frame' is held
while you are dealing with it. The idea is that the dimensions and
magnification of the picture can be completely independant of the
screen resolution. As an example, you may wish to edit a 640*480 GIF
image in a 320*200 resolution at a magnification of up to 4:1, and this
imposes no restrictions or conditions on the way you work.
The only way to explain this clearly is to demonstrate it.
Firstly, we will need to select a suitable resolution. Move the mouse
towards the 'screen-resolution' icon (second row, 4th from end) and
click the mouse. The video selector will appear with the settings
currently being used. Select a screen size of 320x200 and a canvas size
of 640x400 in 256 colours. Right-click to exit the selector and give
Chroma a second or two to re-configure it's memory. You should now have
a canvas area four times the size of your screen, but completely blank.
Click on the disk icon to bring up the file menu, and select '.GIF'
from the formats list. Now click on 'LOAD' to bring up the file
selector and select a GIF to load. Chroma will load the image and re-
scale it to fit the canvas if it is too big. Right-click to exit the
file menu.
Bring the menus back up and click and hold the canvas area.
Dragging the mouse should scroll the picture around inside the screen,
allowing the user to view any part of the picture. Single-clicking on
a specific part of the picture will centre it around the mouse,
bringing it into view. The numeric keypad buttons 1-9 except '5' can be
used to simulate this scrolling trick, and play an important part in
the proper use of the canvas area as will be revealed.
Select the 'line' icon and right click to remove the menus. Now
click and drag a line with the mouse. This dragging technique is how
most of the tool icons are used, unlike the click-drag-click approach
used by some other packages. Now repeat the process starting at the top
left corner of the screen and drag the line towards the bottom right.
The problem here is that you may wish to drag a line or a box across an
image which does not fit into the screen. This is solved in a very
simple way - pressing 'space' at ANY time will centre the screen around
the mouse pointer. This means that you can scroll around the canvas by
tapping the spacebar or using the keypad even while dragging lines and
other such operations - effectively eliminating problems relating to
huge images.
1.12 Parallax adjustable!
The most powerful adaptation of this 'virtual' system is the zoom
function. Rather than having a separate zoom studio, which is clumsy
and inherently very limited in it's range of abilities, Chroma can
change the magnification of the MAIN editing screen at any time to one
of four settings - 1:1, 2:1, 4:1 or 8:1. This is done incrementally
by pressing the 'z' key (or the '+' key on the keypad) to zoom in by
one level, or the '\' key ('-' key on keypad) to pan out one level.
This will magnify the area directly under the mouse, and centres the
image accordingly - i.e. If you wanted to zoom in on someone's eye for
close re-touching, you would place the mouse over the eye and tap the
'z' key a few times. The eye would now fill the screen.
What makes this so useful is the fact that you are not just
limited to drawing or editing during zoom, but have access to ALL of
Chroma's options at any magnification. You can cut, paste and rotate
blocks, draw lines, create gradient-filled shapes, anything you like.
Chroma does not allow the user to turn zoom 'off', you just drop the
zoom level to it's lowest magnification. Zoom mode is not really a
mode, more a sort of parallax-adjustable screen, where the zoom level
is invisible to the operation of the tools. This is VERY useful.
All of these fast key-macros described above can be utilised
during almost any operation - including line-dragging and animation.
It is possible to play an animation in any direction using the arrow
keys, and still be able to zoom in and out or scroll around during
playback without upsetting the system. These global macros are labelled
'WINDOW KEYS' and are detailed under the keyboard shortcut section.
1.13 Remote control.
The Animation side of the program is handled almost entirely via
the menu bar at the bottom of the screen. This can be deceiving since
it does not look very complex, but it can do a great deal. When Chroma
is first run, the user has access to only one screen. This does not
allow for animation, and it would be sensible to think that the program
needs to be configured in some way before this can be achieved. Not so.
To add more animation 'frames', you simply click on the correct
button - situated on the far left or far right of the 'frame bar',
depending on whether you wish to add a frame to the start of the
current animation or to the end. The frame bar is the long strip with
the numbers '1:1' situated in the middle - meaning 'frame 1 of 1'. If
you were to add 3 frames for instance, the strip would shrink to a
quarter the length of the frame bar and the numbers would read '1:4'.
This will make more sense if you play around with it - it is a visual
interpretation of how many frames you have and which one you are
currently viewing.
The left and right arrow keys allow the user to travel backwards
and forwards through the animation respectively, and the up/down arrows
will play the animation back in either direction. This can be simulated
with the '5' key on the keypad to start and stop playback. Drawing on
one of the frames in the animation is no different from dealing with a
single image, except when you move away from the frame and onto the
next, Chroma will attempt to compress the changes made to the image and
store the result permanently in memory. Changes can be undone up to the
point where the user advances to a new frame - past this point the
alterations are not reversible unless the user does the work manually.
Changes made to a frame can be undone at two levels, a simple undo or a
complete recall - undo reverses the last change made (undo is also
self-reversible) while a recall will undo all changes made since the
user last entered that frame.
Up to 4000 images may be held in memory at one time, and all are
compressed by a technique commonly known as 'Delta compression'. This
takes advantage of the likelyhood that each frame of an animation is at
least vaguely similar to the ones before and after it - even though the
start of the animation may look very different from the end. Chroma
needs to store only the differences between images, reducing memory
requirements dramatically.
A complete discussion on this multiple image system can be found
in the section labelled 'THE DELTA STREAM PRINCIPLE'.
2.0 The Toolbox
-----------
[ Pen ] { 1 }
Tool description:
The Pen is the first Icon on the toolbox menu. It is used for
freehand drawing and the touching up of individual pixels, and can
utilise both forms of available BRUSHES (see section on BRUSHES).
Options:
There are three forms of pen to choose from :- NORMAL, STREAK
and LASSOO. NORMAL simply draws solid lines, STREAK draws broken
or fragmented lines and LASSOO lets the user define an area to
fill with solid colour in freehand style.
Also to be found on the options menu is a selection of
system BRUSHES of various shapes, four being user definable.
These brushes also apply to some of the other available tools on
the menu.
[ Line ] { 2 }
Tool description:
The line tool creates straight lines with the currently
selected brush (see above). This tool uses the click-drag-release
technique common to many similar interfaces.
Options: (None)
[ Curve ] { 3 }
Tool description:
This options gives access to a range of four of freestyle
curve methods. All operate in realtime and have access to the
brushes.
Options:
Bezier: A fast and extremely expressive curve requiring only four
key points. The line passes through both the start and end
points, but NEVER through the centre points. A Bezier will
always lie inside it's kite-shaped perimeter. Beziers are
ideal for creating natural-looking shapes like water drops,
face contours and car body designs.
B-Curve: This routine is slightly more intensive and produces a more
digital, less expressive form. Ideal for creating rounded
edges for sharp-edged objects. B-Curves are similar in
operation to Beziers, but are more correct. Both curves use
a drag operation to start, and one drag per point to finish.
B-Spline: An extension of the B-Curve allows any number of points to
be defined (actually 50) This means complex outlines may be
built with the minimum of manual work. This spline form does
not use the dragging technique utilised above, but requires
the user to firstly click the points required. A right-click
will exit this mode and allow the points to be positioned
properly. Another right-click finishes the job.
BetaGon: A sort of B-Spline Polygon. This is an interesting tool which
is surprisingly omitted by many programs, allowing the
creation of closed splines. This means you can click a few
points on the screen (4 minimum) and get anything from a
circle/ellipse to an Indy-500 racetrack! It is most useful
for creating natural forms like fruit, clouds, eggs, faces
and suchlike. We have found it very useful for creating
fonts...
The remaining options offer a balance between speed and
accuracy. Low resolution does not normally require splines using
more than around 250 plots, so FAST mode may be used for more a
more responsive result. Higher resolutions might require 'HIRES'
mode to keep the accuracy up. It is much easier to spot flawed
lines at a higher resolution.
[ Box ] { 4 }
Tool description:
This tool creates filled or outlined squares or rectangles.
There are also a number of extended features available including
gradient and smooth filling. Boxes are defined using a simple drag
operation with one exception described below.
Options:
Square: This forces filled or outlined boxes into the shape of a
square. That's about it really...
Outline: Simply draws the outline of a rectangle.
Solid: As opposed to OUTLINE, this fills the box with the selected
foreground colour.
Gradient: Smooth-shades the rectangle from one colour through to
another. The range of colours is defined by changing the
foreground and background colours on the palette bar, and all
colours in between these two (inclusive) are used to create
the fill. The box is defined by a drag operation, and if
desired, also allows rotation of the texture using the mouse.
Clicking on the screen and spinning the mouse round the
centre of the box will do this in realtime.
N.B. True colour handles gradient fills differently from 256-col
mode, and can produce differing results. For more information
see the 'TRUE COLOUR vs BITPLANES' section of this manual.
QuadGrad: An extension of Gradient fill causes the dragged-box to
examine the RGB colours below the four corners of the
rectangle and perform a smooth 2-dimensional gradient across
the surface. I.E. If one corner is white, one red, one blue
and one green, you will get the correct colours at the
respective corners flowing together to create a rainbow in
the middle. This is useful for smoothing off rough edges in
true-colour. 256-colour mode can produce some colourfully
bizarre results.
[ Circle ] { 5 }
Tool description:
The circle tool draws outline, solid and gradient filled
circles. The circle is defined using a drag operation to define
the radius, and the solid version is performed in realtime.
Options:
Outline: A simple hollow circle.
Solid: A solid-filled version of the above.
Gradient: Shades from the centre of the circle out towards the
perimeter in a semi-circular fashion through a range of
colours defined by the palette markers. (See Box tool)
[ Polygon ] { 6 }
Tool description:
The polygon function creates multi-faceted shapes like
triangles and pentagons, with a number of variations. The points
are defined in the same way as the B-Spline or BetaGon tools -
click the mouse at each point reqired and right-click to position
the polygon accurately.
Options:
Outline: Creates simple wire-frame polygons.
Solid: Fills the resultant polygon with the foreground colour.
TriGrad: Like QuadGrad, except using three points. More controllable
but with slightly different results (straight gradients with
no curves).
[ Fill ] { 7 }
Tool description:
The fill tool flood-fills an area in one of a number of ways.
You may fill with flat colour, a brush texture or with a form of
colour-gradient.
Options:
Solid: A straight solid fill using the foreground colour.
Brush: Fills the shape with the texture held in the currently
selected brush buffer. There are four of these buffers and
are described in detail under the 'BRUSHES' section.
Gradient: Fills an irregular area with a blend of colours starting with
the foreground colour and working through to the background
colour. (see circle and box fills)
The difference is that the fill begins where you click and
fades outwards from there. This is handy for highlighting car
bonnets or anything with rounded, shiny plastic or metal
surfaces.
[ Airbrush ] { 8 }
Tool description: ****
Options: ****
[ Gridlock ]
Tool description: ****
Options: ****
[ Cut brush ] { ESC }
Tool description:
This tool offers a range of ways of lifting screen area into
one of the four brush buffers. The standard way is to drag a box
round the desired area, but this may also be done with a freehand
'LASSOO' operation using the mouse.
Options: ****
[ Clever-cut ] { TAB }
Tool description:
An expansion of [ Cut brush ] means the machine can be made
to do the dirty work. The types available are CLIP, which just
cuts out the used area of the screen discarding the rest, and
LIFT, which allows the user to click on a shape which will be
intelligently cut out from it's surroundings. There are also
provisions for a 'literal-cut' which REMOVES the area cut from the
screen instead of just copying it into the buffer.
Options: ****
[ Move block ] { M }
Tool description:
Blocks can be moved around the canvas for the purposes of
accurate positioning. This does not affect the image, as it is
not meant for pasting blocks as such, just for setting up their
initial coordinates for tweening or later pasting. (See the PASTE
tool and TWEEN-RENDERING for more information on Chroma's tweening
options.)
Options: ****
[ Paste block ] { P }
Tool description:
Blocks can be pasted onto the canvas in either a SOLID form
or with a transparent colour. The transparent colour is usually
black, but is selectable in true colour mode.
Pasting is carried out by selecting the tool and dragging
the block to the correct place. Releasing the mouse drops the
brush onto the canvas.
If one of the TWEEN modes are selected, the brush may be
pasted over a series of frames in the animation, the position of
the brush shifting in the direction of the drag one each advancing
frame. This is a simple interpolation process starting with the
block's initial coordinates and ending at the newly chosen
position. If the process is performed over 10 frames, the distance
moved on each frame will be 1/10 of the dragged distance. Other
tools have access to this feature, as it is a general part of the
system. This ability is the purpose of the 'move block' function
described previously as it is exempt from any automated tweening,
making it easier to position blocks without Chroma interfering.
Pasting is a realtime operation.
Options:
Relative:
The standard positioning technique used for dragging the
blocks around the screen. The block will move relative to it's
initial coordinates.
Absolute:
The brush will be pasted below the mouse at it's top-left
corner. This makes it easier to place things along the top or left
edge of the screen.
[ Paste below ] { B }
Tool description:
Identical to 'Paste block', except the block is placed
'beneath' the canvas. The block will be visible through the
transparent colour on the image. This is also a realtime
operation.
Options: (see above)
[ Flip block ] { I }
Tool description:
Flips the currently held block either horizontally or
vertically, depending on which side of the block you click with
the mouse. Clicking above or below the block will flip it
vertically, while the sides will flip it horizontally. Clicking on
the block effectivley transforms the operation into a PASTE drag
operation, where releasing the mouse drops it onto the screen. The
right button skips the paste option.
Options: ****
[ Stretch block ] { S }
Tool description: ****
Options: ****
[ Rotate block ] { R }
Tool description: ****
Options: ****
[ Distort block ] { D }
Tool description: ****
Options: ****
[ Fit block cols ] { F }
Tool description: ****
Options: ****
2.1 The Frame Controller
--------------------
This menu is situated at the bottom of the screen, just above the
palette bar and is used for the management of multi-frame sequences.
[ Insert frame ] { INS }
Function description:
Used for creating/duplicating image frames. Two of these
icons exist, sitting to the left and to the right of the frame bar
respectively. They are represented as 'down+right / down+left'
arrows and simply insert a copy of the image either before or
after the current one, depending on which icon is chosen. This
feature is used for adding frames to the start/middle/end of
animation streams. Using the right button forces the addition of
ten frames rather than one for faster frame creation.
Options:
Left mouse = add one frame
Right mouse = add ten frames
[ Frame control bar ]
Function description:
This bar is only available via the mouse, and allows the user
to 'run' through the animation by dragging the frame indicator
button to the left or right of it's position. The position of the
button on the bar is an approximate indication as to where you are
in the animation, regardless of it's size. This is similar to the
slider bars you find on the window borders of some GEM programs.
[ Clear/Delete frames ] { DEL }
Function description:
Used for clearing or deleting single frames or frame clusters
from the animation stream. Clearing a frame simply fills the image
with a single colour (background colour). Deleting a frame removes
it from the animation entirely, reducing the frame count by one.
If TWEEN mode is active, the user may be requested if either
some or all of the frames are to be deleted. This is available for
the purpose of removing 'pieces' of film from a larger animation.
Options:
Left mouse = clear screen / fill with selected background colour
Right mouse = delete a frame or series of frames from an animation
[ Tween mode ]
Function description:
This icon is to be found at the very bottom-left of the frame
control bar and contains the letter 'F' as default.
The tween option is for configuring Chroma's tools to operate
not only on the current frame, but on as many frames as the user
wishes. If, for example you wanted to create a morph-animation 15
frames in length, you would use this feature to tell chroma to
render over either one (F)rame (default), (A)ll frames or a
(S)egment of frames with a user definable beginning and end. Since
'Frame' and 'All' modes are automatic and rarely need to be
configured further, Chroma can just get on with the job. 'Segment'
mode however, requires the user to define which frame on wich to
begin and end. This is done by right-clicking on the icon and
dragging the frame bar to the correct starting frame, clicking on
the presented 'START' button to record it. Now drag the bar to the
frame on which you wish the rendering to stop and click on the
'END' button. The frame segment has now been properly defined.
Many tools including Morphing, Pasting, Rotation and
suchlike can make use of tweening. A dialog box will always warn
the user of such a process as it is irreversible once activated.
Options:
Left mouse:
'F' = Single frame render (default)
'A' = Render over all frames in animation
'S' = Render over frames (A) to (B) inclusive, with both (A) and
(B) being definable via the options menu.
Right mouse:
Options menu : Define the start/end of a tween segment...
Move to frame (A) and press 'START' to record the frame number and
move on to frame (B), pressing the 'END' button to record this
frame number. This is only required for (S)egment rendering.
[ Speed controller ]
Function description:
The speed control slider simply allows the user to fine-tune
the playback speed of an animation. The nearer the button is to
the left of the bar, the faster the animation will play.
N.B. Due to the speed and bandwidth of the Falcon's data-bus, copying
very large chunks of memory around can sometimes be a little
sluggish. Since a 640*400 true-colour screen (512k) can be
considered a fairly large chunk, some larger animations have a
maximum play-speed of up to 10 50ths/sec, especially at some zoom
levels. This does not affect the SCALE of the values available on
this bar, just the upper speed LIMIT of an animation.
[ Move/play left ] {left arrow key/up arrow key}
Function description:
There are two of these icons, one for left and one for right.
Using the left mouse allows the animator to travel one frame in
either direction. This can be emulated with the 'left' arrow key.
Using the right mouse button causes the animation to be
played in either direction. If ping-pong is activated, the
animation will reverse direction each time it hits the first/last
frame. This can be emulated with the 'up' arrow key.
It is MUCH easier to use the arrow keys for these operations,
as they tend to be very heavily used when working with anims.
Options:
Left mouse = move one frame to the left
Right mouse = play animation backwards
[ Move/play right ] {right arrow key/down arrow key}
Function description:
[ See above ]
[ Jog shuttle ]
Function description:
Much like the kind found on modern video-recorders, this bar
lets you 'walk' through an animation in any direction and at any
speed. The button's resting position is in the middle of the bar,
and can be pulled left or right to animate either backwards or
forwards respectively. The distance the button is pulled from it's
resting place decides how fast the animation plays in that
direction. Slight movement causes slow playback, while pulling the
bar to it's limit plays at full speed. The button will spring back
to the centre when released and animation will stop.
2.2 The Morph studio
----------------
Due to Atari's surprising inclusion of a DSP56001 processor,
operations which would normally take hours can now take minutes and
even seconds. The DSP's sheer numbercrunching power can outperform
numerous processors even running at double it's own clock rate, which at
32MHz is far from slow. This allows the implementation of extremely
silly software normally restricted to large machines such as Silicon
Graphics Indigo, Iris and SGI3D/4D workstations.
We do not let this extensive power go to waste...
Chroma contains a system known as 'Field-warping' which allows
the user to create magnetic fields in the form of control lines with
which an image can be bent, twisted, melted and distorted in any way
possible. The results to be gained from this have to be seen to be
properly appreciated, but they are often very amusing, and in
conjunction with Chroma's ability to 'tween' most of its operations,
some very wierd animations can be created.
More importantly, Chroma can make use of Field warping to 'Morph'
two independant images together to create a third. This is quite common
on T.V. and can be seen in many recent films. 'Terminator 2' and 'Super
Mario Bros.' make use of this system, as do a number of T.V. adverts
including the 'Castrol' advert - involving cars changing shape every
few seconds. The 'Black or White' music video used Morphing (Field
warping specifically) to change one person's face into another, and
these are just a few obvious examples. The limits are really only set
by the amount of RAM you own and what you can come up with.
There are a few rules applicable to the morph studio which
are simple enough to grasp :-
1. The Morph studio is effectively useless with less than 2
frames available. None of the functions will work. At least 2
screens must be present for the line-tweening operations to
be effective, including the definition and positioning of the
control lines.
2. Morphing can only work in true colour. It involves cross -
fading images using RGB techniques which are slow and
cumbersome in anything other than true colour. If you wish to
create a 256 colour morph, render it in TC mode and convert
it down to 256 colours afterwards.
3. The above rule does NOT apply to controlled distortion since
it requires no RGB balancing and therefore needs no more
colours than the initial image contains.
To create a distortion or morph, the user needs to provide
Chroma with some source material. Distortions require only 1
source picture, but at least 1 other screen is needed for storing
the result. Morphs require 2 source images (first and last frame)
and at least one other frame in-between for storing the result. If
you wish to render an animation rather than a picture, you will
need to insert many extra frames in between the two source images,
giving the tweening system somewhere to put the results.