Inferno #10 30 апреля 2007

Железо

Future Spectrum - Video Display V9990. Enhanced graphics capabilities ZX Spectrum.

  One of the ideas advanced graphical
opportunities for ZX Spectrum, put forward by
The latter time is the use of chip
Video Controller V9990 (used in
graphics card GFX9000 for MSX). This
article was written to highlight opportunities
chips in this class, the prospects of
V9990 on the ZX and compare its features with
graphics capabilities of the popular 8 - and
16-bit game consoles.


     The device of graphics subsystems

              on consoles


   Platform video end of the 70 -
mid-90's are independent
Indeed subsystem having in his coc
Tave Video Controller (VDP, Video Display
Processor), video RAM (VRAM, and possibly
VROM), as well as some additional elements
(ColorRAM, VideoDAC, etc.) that can
or be part of the VDP, or a separate problem
PAMI. In this case, the internal resources videosi
system (in particular, memory) prices available
tral processor napryamuyu.Vmesto this
video controller is connected to the processor through
I / O ports - through them
data to be placed in video memory and control
resistivity video controller. For processors
no I / O ports - such
majority, and among them, for example, often
applied in 6502 consoles - port
video controller displayed in the address
memory space. VDP can also gene
erate interrupt to the processor, as mi
minimum is at the top VBLANK, and sometimes for several
Other important events - the beginning of the map
skanlayna, collision sprites, excess
limit on the number of sprites.

   The main feature of such videosis
so is the lack of raster videore
regimes that are typical for computers - in which
Each point has its own address in videopamya
Tea and can be arbitrarily included or
OFF (APA-modes, All Points Address
able). Instead, the approach used
when storing and displaying graphics
data are fully engaged in video surveillance
ler, and the central processor only issues
his team - where and what to display. Similar
proach can work effectively
with a complex two-dimensional graphics (stable
50/60fps, so loved by Speccy) in the Neva
sokoy the performance of the pro
core processor. Subsequently, with increasing power
processors (mid-90's and beyond) in the VDP
began to appear and bitmap Modes
(Eg, Gameboy Advance).

   A couple of words used in the text of the ter
mines. As can be seen below, a single
terminology is not, but usually the organization
video mode, which is typical for platformers
VDP, called a 'tile'. Also meeting
are the names' block schedule ',' pattern
modes'. In this text I will use a ne
rvy option. Values ​​and other options
terms will be explained in the course text.


               Features

      platformers videocontrollers


   VDP can have one or more of the form
deorezhimov distinguished, in addition to authorization,
available services in these capacities. Bu
deorezhimy all platformers VDP build
Camping on the same sheme.Izobrazhenie Sobir
is a set of strata (layers).

   The bottom layer - is always the backdrop
(Backdrop), something like a curb on the Speccy,
but occupies the entire screen area. Unique
thing is that you can do with it - change it
color. The back can be seen in the presence of
'Transparent' (not derivatives) seats in the remainder
lnyh layers. Thus, if
desires can be realized effects analysis
logical effects on the curb ZX, on the whole
area of ​​the screen, with the help of transfer values
of only one register, defining
color backdrop. It is possible to ask
area of ​​effect using the mask of an arbitrary
quadratic form (made from the background layer with the 'Prose
rachnymi 'and' opaque 'points).

   This is followed by layers of one of the two types
types, their set differs for different VDP.
Sequence of output controlled system
priority theme, which also happens once
Noah (always present).

   The first type - the layers of background graphics. By
terminology of the late 70's they were called
playfield (abbreviated as PF, PFI, PFD), in the 80
they became known as background (BG, BGD). Kage
dy a fiber collected from the monospaced
elements almost always have time
measures 8x8 pixels. These elements are called
very differently: tile (tiles, slabs
ka), characters (characters, CHR), blocks
(Blocks), cells (cell), or patterns
(Can be translated as 'pattern'). Schedule op
mined by the appearance of these elements, customs
chno called the pattern, or character. Tiles
form a two-dimensional matrix, each cell
ka which contains the block number of graphics and
certain flags (usually 1-2 bytes per cell
ku). The matrix size is measured in quantitative
ve elements, and may be equal or pain
PWM (2-4 times) than the area of ​​the screen. In
the latter case, the screen is visible only
part of the matrix. VDP allows you to choose to
chalo display the background layer up to
pixel, which enables rapid
'Scroll' - you just change the value
radiation bias layer in the register and record
vat in the invisible at the moment of the bu
Schrieffer new string columns, if the level is not
placed in the buffer background. Many 8-bit
GOVERNMENTAL consoles, for example, NES and Sega Master
System, the buffer size is the size of the background
screen, so sometimes it can be seen as
extreme columns of the background 'being completed' in
dvizhenii.Obychno derivation layer zatsiklivayas
is, ie, if you ask important
bias, on the other side of the screen will
visible to the opposite side of the layer. Displace
blocks relative to each other typically nel
SC. Nevertheless, sometimes such a possibility
present but rare (there is a Sega Mega
drive / Genesis). used in 8-bit
and the first 16-bit consoles were VDP
only one layer fona.Bolee later VDP solution
is realized more layers - 2, 4.
These layers are independent from each other and can
Gut 'to scroll' apart from each other.
Matrix describing the layer is stored in the form
deopamyati, along with graphics tiles themselves.

   The second type - the layers of sprites. Any
prefixal VDP enables
display hardware sprites. Each
Sprite is a separate layer. Priority
O determined by the number of sprites layer
a priority among sprites and backgrounds - a system
topic priority. Size sprites depends
the capabilities of specific VDP. It can
be fixed (often 8x8 or 8x16)
or choose from several available
(Usually no more than 64x64) - usually
for all sprites at once. There is also a
a small number of VDP with the possibility of
destination size (from several access
ones) for each sprite separately. Graphics
Sprites are often constructed from the same block,
that the background graphics, in which case they represent
represented a single unit grafiki.Koliche
the set of sprites are always limited by the apparatus
inverse VDP capabilities on two parameters
frames - the number of sprites are displayed
on the screen and the number of sprites, finding
schihsya one skanlayne.Pri this value
the second parameter is usually much smaller
first. If you exceed the limit on sprite
skanlayn 'extra' sprites in this skanlayne
just not displayed.

   Graphics tiles and sprites may contain
reap 'transparent' pixels that transmission
intersect in the derivation - instead displays
Xia content of the lower layer (another valid
one background, backdrop).

   Most of the VDP has limited capacity
opportunities for the display of color. Usually this
palette or a set of palettes, the colors in which
chosen from among the available ones. Palette
may be one for all layers, may be
two palette (background and sprites) can
be greater. Often found the opportunity
assign each sprite and background elements
one of several palettes available. If
celebrates the 'cells' in the palette and the number of dos
sources available to select colors defined by WHO
possibilities VDP.Pervoe number usually Nevel
to, and the more separate palettes available
- The smaller the cells in them. The second number for
depends on the scheme for forming the final CEE
ta - 16 colors to 16 million colors
(Typical values ​​- 16, 64, 512, 4096, and
etc.). It is important that the palette does not tied
to a specific schedule of tiles or sprites
that allows you to create different effects
by changing the colors in the palette. In English
lingual terminology used in the following
ing names: palette - the actual palette,
or CLUT (short for Colour Look-Up
Table); color in the palette - palette entries,
logical colours; available for selection in CEE
ta - just colours.

   In addition to these major possible
Stay available to each VDP, may be
Additional vozmozhnosti.V particular, this
'Mirroring' sprites or tiles, then
a reversal of their vertical and / or
gorizontali.Inogda found ability
partly (in some areas) to prohibit
scrolling background layer that is convenient
for organizing the panel game statistics.
Especially advanced VDP, for example, video
System SNES, have the opportunity to mix
background colors and sprites (hardware semi
transparency, alpha blending), scaling
and rotation of layers background or sprites. Another
useful, but not always available may
Stew (in particular, is a sore point Ac
tavok Nintendo) is to identify factors
is the collision of sprites - imposing their
each other in such a vyvoda.Esli
option is present, it is almost always
works' pixel by pixel, "ie, the fact of the collision
veniya determined by the real application of
each other 'opaque' point is valid
Comrade, rather than by coordinates.


          Hardware limitations

             and overcoming them


   Compared with the raster video mode
MI, particularly with linear organizations, WHO
possibilities seem limited block graphics
chennymi. And it really tak.Pristavo
chnye videocontroller oriented operating system
mainly on rapid withdrawal of a simple two-dimensional
graphics. Therefore, the realization of such things
such as wire or polygonal
graphics, they are very difficult for the CPA
vneny raster video modes (one
to the still possible). In addition to the restrictions
imposed by the approach of block graphs
VDP have some hardware limitations. On
simple VDP these restrictions sometimes very
important, but some of them may be about
yti using different software tru
Cove and the use of hardware singularities
Tay specific VDP.

   The size of sprites, most VDP bounded
1.2 model is bounded in size, usually the order
dka 8x8 ... 16x16 pixels. Because many
Games require facilities larger
They are made up of several sprites.

   Restriction on the number of simultaneously
display sprites on the screen can
circumvented by changing the position and type of sprites
beginning of each line of this triangle rastra.Dlya
buetsya or the presence of interrupts HBLANK,
or exact synchronization program. On
Practice this trick was used extensively
only in the early consoles, where the number of
Sprite has been extremely limited (NAP
Example 2 - on the Atari 2600), he subsequently
became less frequent. In the terminology of MSX
This technique is called sprite-split.

   Restriction on the number of colors, which
rye can be used within one
sprite, in principle, can be bypassed by bringing
several sprite on top of each druga.No on
practice a similar technique was used to
fairly rare - in systems where its at
variation of it may be necessary, restrictions
the total number of sprites on the screen and
the number of sprites on the same line
also very tough.

   Restriction on the number of colors, one
temporarily displayed on the screen can be about
yti same way, changing the palette
the passage of the beam to the desired row races
spectrum.

   Chief of the limitations, of course, is
Limit the number displayed on a single
skanlayne sprites, especially at small
spraytov.Naprimer amount, for the NES may
display only 8 sprites (with a width
Noah 8 pixels each) on skanlayn. Many
or a little? For games with a vertical to scroll
Ling (such as Flying Shark, Road Fighter)
it is not very critical constraint in their
situation with a large number of objects on
a horizontal line appears Nechay
hundred. For more typical platformers games -
'Begalok' - this restriction is
problem. Assume that each character
(Hero, enemy) has a width of 16 pixels (2
sprite). Enough of all three enemies at
same height as the hero, to exhaust a
mit, and any effect that uses sprites
(Explosion, a bullet) will exceed it. At excess
limit of sprites on skanlayn all 'unnecessary'
sprites, just not displayed. Avoid
similar situations in the games are traditionally difficult
Indeed. This problem can be solved the totally
Tew, and no tricks will not help. But
can reduce its impact on gameplay.
The essence of the decision to change the sequence
Tee sprites on each kadre.Pri exceeded
limit in a single frame lost one piece
sprites, each other. Will visually
observed an artifact in the form of flickering is valid
ytov (it can be seen in virtually every
Doi game on NES), but no object of
fall completely. This technique is called
sprite multiplexing. Also, many VDP, y, and
NES including the funds are indications
'Importance' sprites - which cast
exceed the limit in the first ochered.Eto
avoids flicker the most important
jects, such as the protagonist.

   Most of the VDP for 8 - and 16-bit
systems are not able to display the floor
transparent objects (alpha blending). AND
Unlike systems with raster videore
zhimami, they are almost impossible to Rhea
formalize this effect reaches programmno.Dlya
tion effect using 50% translucency
form a very simple trick. It is possible to
any systems that bring the image on the
TV. Object runs in a grid of points
in a checkerboard pattern - a point graphs, blank
tochka.Iz to the low-definition images
on conventional TVs adjacent points it
Nogo merge and create the effect of semiconductors
transparency. The higher horizontal resolution
solution of the system - the effect looks better
fekt.Takim way made the bushes on the ground
level in Sonic 2 and line power fighters
in Mortal Kombat 3 on Sega Megadrive. Similarity
bny same approach is used in ZX, for
create intermediate shades
(Hatching). Slightly less common other
way to simulate translucency, it is usually
applied on the slot machines, which
Vertical Frequency is usually equal to 60
gerts.Osnovnaya idea remains the same - the dashed
hovka in a checkerboard pattern, but each frame
opaque and transparent points change
places. Of course, there is a glimmer of an hour
totoy 30 hertz, but this frequency is sufficient
high that it was not very noticeable, but
the whole effect looks better, because
individual points are less shading
zametnymi.Takoy effect of active use
lsya, such as Street Fighter Alpha (Zero)
3 on a slot machine CPS-2.

   The most difficult to circumvent the restrictions
Niemi was the idea of ​​block schedules -
if required, for example, to implement the vector
rnuyu schedule. However, this limitation can be
around a number of ways, depending on the in
zmozhnostey specific VDP. If the system
has enough memory and can dos
sufficiently fast to transfer data into it from
processor, you can simulate Bitmap results
Assume assigned to each 'familiarity' background
tile with a unique number, and draw nuzh
nuyu graphics directly in the images taylov.Na
systems where memory is not enough to
storing images full screen, you can
complicates the rendering algorithm to Phragmen
Options of the image, where the presence
exist in a different color, fit into the available
memory, and for areas with the same color is called
started the same tile. Similarly, the formation
Thus, for example, implemented in the game Elite
NES. Of course, such decisions can not be
called simple, but the use of ve
ing is not for its intended purpose is always to
conjugate with some difficulties.


       Typical graphical effects


   For all of the above might give the
the view that the VDP is a single
continuous limit. Of course, it is not,
There are emotional moments. In addition to its direct
Mykh responsibilities for the rapid conclusion 2Dgrafiki, VDP 
provide the opportunity of simple implementation of a number of 
effects. 

   The most interesting opportunity explosion
us to technique, which has the name of the raster
effect. Also found the name of the line
scroll, but it is commonly used to
specify the additional hardware for
support, simplifies the implementation effektov.Sut
This technique consists in changing the bias
layer (or layers) background on each of the rows
raster. Hardware support is
the presence of pointers for each of the bias
strings that can be set once for
frame. In the absence of such support mixed
generalization background will have to change manually
HBLANK or with precise timing
programmy.Poetomu effects of this type rarely
occur on systems that do not have generators
tion interrupt HBLANK.

   Most often used linescroll
to implement the so-called parallax
scrolling'a. This method of creating an apparent
the depth of the scene by scrolling (typically
only horizontal) of its parts with different
speed. For example, the land surface in
game genre 'platformer' (for example, Sonic
or Mario) is moving quickly, and not a cloud in the
Be - slowly. Depending on the number
background layers, supported by VDP, the effect is
limitations. So, if there is only one
layer background scene is divided into a number of horizon
lnyh bands, each of which has its
speed of movement, and objects from one
bands can not go to another lane.
However, this can be circumvented by bringing part of the union
projects sprites. This decision of the trial
lems are often used to console PC
Engine, as its VDP supported sprites
rather large razmera.Pri the presence of two
and more layers of background limitations become
less serious - they are saved to the SC
zhdogo of the layers separately, but the layers
have separate bias. Near-bed
displays the basic background play, moving with
one speed, and at long run
the desired effect. This principle is used
In most games on the Sega Megadrive / Gene
sis. To see whether there are restrictions in this
case is not easy - so, in the first levels of games
Sonic the Hedgehog 1 and 2 or Rocket Knight
Adventures in the said console for ne
moat glance it seems the presence of
huge number of background layers, and only
Looking closely you can see that it is not
so.

   You can create and other effects of
by linescroll. For example, the effect of shaking
of hot air. To this end, the total
shift of the background layer is added, say,
sinusoid, a small additional shift
of. In the case of two or more layers of background
effect can be used as all or
and one of them (front or rear,
depending on the ideas). More rarely
effects occur with a change in Vertical
lnyh bias, since not all have the VDP
opportunity to change the vertical displacement
of background at the time of passage of the beam raster.
Due to changes in vertical displacement
can realize the effect of stretching or
distortion of the background layer vertically. Combining
change the horizontal and vertical
displacements, we can get more complicated
effects.

   This same technique can be used
and to solve such problems as rendering
slopes at polutrehmernyh races (such as Chase
H.Q. ). Actually, the principle of giving
flat track prospects in those games
called scanline-based, but in general the technique
called sprite-based (because objects
in such games are sprite)
or scale-based (because the sprites for
derivation mastshabiruyutsya). Linescroll in the realization
tion output track in block mode when
changes for vertical priest
selnoy precision output tiles, allowing the
make the size of tiles 1x8 instead of 8x8. Each
Dai horizontal line 'texture' doro
Ki is stored in all possible horizontal
GOVERNMENTAL scale, and to derive the desired scale
chosen change the bias of the background layer.
It is noteworthy that the effect of motion on the expensive
n the first racing games to use
eat this technique was implemented through the anisotropic
mation palette (see below).

   The effects of the change palette. That those
nickname is sometimes called the Palette-Shifting
or Palette Animation and can be used
tsya on any system in any video mode
Max (not just block), which displays
Color images are defined by programs
Fix a palette, rather than directly
color values ​​for the points rastra.Osnovnaya
The idea is that when the
values ​​in the palette immediately change
color in the displayed image. At the same time
does not require changing the actual data
Graphics - for bitmap mode without firing
algebra in order to achieve a similar effect
would have to go through all the points of the raster.

   Conditionally Grayscale effects can be separated
divided into two groups. Feature of the first -
change all the colors of the palette directly. Nai
more typical effects of this group - 'The Fairy
ding '(fading, the word fade -' Fade Away '
'Damping') image. That is, smooth
quenching and the appearance of the screen from black or
white to the normal image, and
vice versa. It is also possible gradual bleaching
the same valuation images or change color
gammy.Smena range can be used to
For example, for the underwater scenes - when the hero
falls into the water, you can smoothly change the parameters
liter, adding more blue tint, but to
Then he was chosen on the surface - to return
normal palitru.Takim same way we can
implement the change of time of day (such
effect is realized in the Fantastic Dizzy). When
This chart itself does not change in any
modification of the scene from one common
same set of graphics.

   The second group palettized effects differ
differs only part of the change of colors in
palette, it's own animation with the help
soup palette. It is used to change
colors of individual objects. For example, for
'Flashes of lightning' in the background; glow
shots from the night scene, for flashing
enemies with bullets hit them, for ignition
Gahnia stoplights at cars; animation
surface water or lava. The same group
You can include discoloration of the characters
using a single set of graphics -
this may be changing colors for the boss
depending on the rest of his energy or
superficially similar, but different colored enemies
(Typical of games in the genre and beat'em'all
shmup'ov). This same method can be realized
vat brightness change character depending on
dependence on whether it is located under the source
light or in darkness.

   The effects of a change of graphics tiles.
Animation of objects on VDP can be realized
in two ways. Is commonly used replacement
on the number of displayed blocks of the background or
sprites. It is fast and logical way.
However, it is also possible to replace itself and the boundary
fiku blocks. This method may be more
slow (depending on the volume changing
emyh data), but it can be realized
vat some effects. For example, the VDP with
a background layer can be implemented ef
effect of the second layer of parallax scrolling.
The second layer in this case is to
bout a simple repeating pattern of a small
size, for example, 32x32 pixels. For the creation
the effect of simply making use scroll
the original graphic pattern in the right direction
and with the right skorostyu.Takzhe with this
method can save the video memory in the case
case, if it is not enough - for example,
necessarily store all the animation frames
protagonist games platformer in videopa
cards, an can be forwarded to the desired frame in the
the same blocks allocated to one
frame image of the hero. Another possible
application of this technique - progressive singing
resistivity or the disappearance of the background image.
To do this, when the loaded map tiles
need to send graphics tiles in videopa
rumple not all at once, as, for example, line by line.



             Features

        Some platformers VDP


   Nintendo Entertainment System (1983)


   Video capabilities of the consoles
interest primarily because of the fact that
the mid-90's it was connected to
Spectrum'u. While this tandem in series
do not receive special popularity.
The current idea of ​​connecting to the V9990 ZX often
compared with this development. After Lake
nakomleniya with the characteristics of the VDP model
zhno will be good to feel the difference.


   Resolution: 256x240. Really much
seen in the PAL overscan, can be seen only in NTSC
256x224. It is possible to turn off updates
tion screen below this region to increase
performance of video memory.

   Video Memory: About 2 KB (buffer background, Pa.
liters sprite descriptors - physical pa
znyh devices, the buffer can be a background
cluded ROM), 8 KB VROM for graphics (at
cartridge bank switching theory
allows an unlimited amount). Reading from a
opamyati needed to make a double, the first
Reading returns incorrect data. Jobs
video memory is only possible within
VBLANK. Working with Descriptors sprites WHO
possible through the DMA.

   Sprites: 64 on the screen, the size of 8x8 or
8x16 (all the sprites of the same size), 3 colors.
Mirroring horizontally and vertically.
Maximum of 8 sprites on skanlayn.

   Background: One layer. Tiles 8x8, 3 Color
on the tile (there is a limit on the choice of colors
for groups of 4x4 tile). Buffer 32x20.

   Palette: 53 colors, are simultaneously
25 (+ 4 flat panel and 3 color tie
fishing + 4 palette of 3 colors for sprites).

   Scrolling: Yes.

   Collisions: None.


   The chip is designed specifically for police officer
ki, by Ricoh. Has a formal code
notation RP2C02-RP2C07 (different version)
actually met marking 6538, TA03
(Apparently invented out of my mind malignant ki
Thais). Some individuals ut
approves that it grew out of TMS9918.Vozmozhno,
this is true, but in fact
almost nothing in common between them. Has
quite a tricky device, because of what it
parameters were difficult to describe in
brief summary vyshe.Est large quantitative
in the intricacies, including arising out of
opportunity to have as part of the cartridge to
additional devices, including bells and whistles
for graphics (and they really
used). Only one tile form
orezhim.Chip not interrupt Scanlan
Well, only NMI on VBLANK. Nevertheless,
line-scroll in games met, probably for
by keeping the program pauses. There
to determine the position of the beam through
'Sprite # 0 hit detection' - check, I'm tired
pouring when passing the beam through the visible
(Opaque, the background under it necessarily
must be set non-zero color)
part of the first sprite in spiske.Eta possible
sequence was used to ban skrollin
ha part of the background to the game stats, for example,
For example, in Super Mario Bros. (Sprite # 0 - this
flashing coin in the panels on top).


        Sega Master System (1986)


   The first exit Sega to market home form
deoigr, virtually unnoticed by us -
because of not very successful competition with the NES.
Many games with a Sega Megadrive / Genesis vyho
Dili and for this system, among them - the 8-bi
tnaya version of the game Sonic the Hedgehog.


   Resolution: 256x192 (256x224, 256x240 in
depending on video mode and PAL / NTSC).

   Video RAM: 16 MB.

   Sprites: 64 on the screen, 8x8, 8x16,
16x16 (all the sprites of the same size), 16
colors. No mirroring. Maximum 8
sprites on skanlayn.

   Background: One layer. 8x8 tiles, up to 448
pieces (limited by the amount VRAM), 16 colors.
Buffer 32x28 tiles, tile mirroring
vertically / horizontally.

   Palette: 64 colors on the screen simultaneously
but 32 colors (16 + 16 sprites background).

   Scrolling: Yes, possible partial
scrolling.

   Collisions: Yes, just the fact the intersection
radiation of any two.


   Special chip, code notation
cheniem 315-5124 (within 315-5246), developed
oped Sega for its 8-bit arcade
avtomatov.S some changes using
localized in the Game Gear (pocket version at
rate, chip 315-5378). Similarly, NES, cha
one hundred mentions that it is based on
TMS9918/9928. TMS9918/9928 used
in MSX1, Coleco Vision and earlier machine
tries from Sega - SG1000 in console and computer
Tere SC3000. In fact, the total a bit.
Equal number of small things, but there are more differences -
9918 did not have the scroll and the definition of one hundred
lknoveny, supported only 32-color
Sprite, a fixed palette of 16 colors
and one background layer with similar Spectrum'u
characteristics.

   Only tile and text video mode
we do not have raster video mode. Horizon
flax scrolling always with the 'artifact' in
left column of the screen (7 pixels). This
column or a background color, or the case
experimental data from the graphics sprites videopa
myati. Chips 'partial scrolling' is
tsya the ability to disable the horizontal
scroll to the top 16 lines, which usually
displays game statistics. Arbitrary
area to scroll nelzya.Izmenyat value
vertical scrolling in the process of mapping
expression can not be shot, horizontal measurements
nyat possible. There interrupt VBLANK and
skanlaynu.Takim way line-scroll perturbation
wives, but in games he almost never used.
Despite all the constraints, the schedule vyglya
leads neploho.V recent games (especially on
Game Gear, which stayed on the market
a little longer) - much better than NES, due to
more colors.


      PC-Engine/TurboGrafx 16 (1987)


   The first attachment, which brought in the house igro
Cove 'true 16-bit graphics. " It
because it was advertised in due course. Gra
Fick's on it really was the best medium
Director existing at the time of game systems
topics. Many colors, big sprites in games
active use of parallax skrollin
ha - all that was to become the continuous
mennymi attributes of 16-bit games. Also
(One year) - the first game console with
CD-ROM.Spetsialnoe retreat for bow
nick Amiga: console and a computer - different
things and different categories of users;
Amiga, and other popular computer in Europe
panthers were not common in Japan, there
There was a lot of their up
machine interface computers without going beyond the limits
ly of the country.


   Resolution: Programmed with the steps in
8 pixels, up to 512x240. Mainly used
We used 256x224.

   Video RAM: 64 MB. There is a DMA in
VRAM.

   Sprites: 64 per screen sizes 16x16,
16x32, 32x16, 32x32, 32x64 (for arbitrarily
each sprite). 16 colors in a sprite. From
zerkalivanie vertically and horizontally.
A maximum of 16 sprites on skanlayn.

   Background: One layer. Tiles 8x8, 16 CEE
Comrade on the tile. The buffer size variable, from
32x32 to 64x128 (several options).

   Palette: 512 colors (some duplicates
be) on the screen simultaneously to 482. 16 Pa
liter for sprites, 16 for background tiles;
Each palette of 16 colors (each valid
ytu and tile can be assigned to any of the
16 palettes).

   Scrolling: Yes.

   Collisions: Yes, sprite # 0 with the remaining
GOVERNMENTAL sprites.


   Special 16-bit chip designed
Hudson for this console. Unlike
other consoles that have taken VDP in a single chip,
divided into two chips: HuC6260, VDC (Video
Display Controller) and HuC6270, VCE (Video
Colour Encoder - everything associated with firing
Roy and video output). Has advanced
interrupt system by VDP: on VBLANK, on
the end of DMA-transfer, to achieve the indicated
zannogo skanlayna, the limit is exceeded
sprites on skanlayn on collision valid
yta # 0 with any drugim.Takzhe in the system is
timer (6992 Hz, 7-bit counter) and pre
on closing on it. Values ​​can scroll
to change at any time, which leads to Nema
dlennomu changing display, and together
system interrupts allowed to create
All types of effects line-scroll. In some games
met complex effects such as scaling
derivations and withdrawal filled rectangles
(Eg, spinning and growing
triangle, evolving into a multifaceted
circle, declining to a point on the letter I in
logo company Taito, the game of which encountered
chalis on PCE).

   It was subsequently released on a pro
will move version of the console - SuperGrafx
(1989). She had just two GPU -
twice as many sprites, background layers, videopa
cards, an at the same CPU on
the same frequency. The result came only
6 games with support for advanced graphics
opportunities, sell consoles fast light
rnuli. Follow TurboDuo (PCE + CD +192 MB
Memory, 1992) again had a single chip.


      Sega Megadrive / Genesis (1988)


   This prefix is ​​sometimes called the 'incomplete
valuable 16-bit ', because it has a relatively
relatively weak in features, but a quick
VDP. Nevertheless, in general, this its' incomplete
notsennost 'less similar to that of PCE (has
lice reverse bias balance VDP / CPU) for
by 68,000 as the main CPU.


   Resolution: 256x224, 320x224 (as in
zmozhny interlaced modes).

   Video RAM: 64 MB. There is a DMA in
VRAM; DMA from main memory to VRAM (in
time VBLANK, 7380 bytes).

   Sprites: Up to 80 on the screen, depending
on video mode. Size from 8x8 to 32x32, 1916
colors. No mirroring. Up to 20 sprites
on skanlayn.

   Background: Two coats. Tiles 8x8, 16 CEE
Comrade on the tile. Buffer size change background
Writable, from 32x32 up to 128x32. Mirroring
tile vertically / horizontally.

   Palette: 512 colors, 64 on the screen. 4
palette of 16 colors.

   Scrolling: Yes, separate the layers,
possible partial scrolling.

   Collisions: Yes, just the fact the intersection
radiation of any two.


   Special chip, which is strongly
Developed version of the VDP Master System.
Is designated as 315-5313.V has added
Ny new video modes, with partial preservation
Niemi old - was created with the console when
Overall, backward compatibility, all the old
iron is present in it, and using special
differential adapter can be used
Games by SMS. Bitmap Modes of pre-
reap absent in older have a number of differing
chii, because of which about a dozen games by SMS
work incorrectly.

   Interrupt system remained unchanged, at
VBLANK and skanlaynu. But separate to scroll
Ling has evolved - can th
horizontal scrolling each skanlayna,
horizontal scrolling for each line that
ylov; vertical scrolling column in two
tile width. One of the layers can be
window without scrolling. Accordingly, linescroll hardware, and 
in two layers of pho on, which greatly facilitates the creation 
of related with its use of effects.



              Super Nintendo

       Entertainment System (1990)


   Full 16-bit console, with power
GOVERNMENTAL audio and video systems, but rather
weak processor - 65C816 (enhanced
to 16 bits 6502).


   Resolution: 256x224 to 512x448. In
mainly used 256x224 (at least
320x224).

   Video RAM: 64 MB. There DMA, allows
move small blocks of data in the VRAM
during HBLANK.

   Sprites: Up to 128 on ekrane.Razmer from 8x8
up to 64x64 (only two different on-screen)
are built from blocks of 8x8, up to 128 colors on
sprite. Up to 256 pixels per skanlayn, otze
rkalivanie horizontal / vertical.

   Background: Up to 4 layers. Tiles 8x8, 4
up to 256 colors on the layer in different modes.
Buffer under von 64x64, distributed over
depending on video mode.

   Palette: 32768 colors, up to 4096 on the screen
(Not taking into account the effects of alpha-blending) to
256 on skanlayn. Up to 8 palettes for the background layer.

   Scrolling: Yes, separate the layers,
with some restrictions.

   Collisions: None.


   The chip is designed specifically for the SNES, about
ducer and the name is unknown. Quite
non-specific characteristics listed you
above, explains the presence of a large koliches
Twa video modes (8 pieces). In addition to the resolution
of, they differ in the number of available
layers of the background and the number of colors on the tile.
For example, in the mode MODE0 available four
layer, 4 color tile, 8 palettes
(32 color). In MODE3 available only two
layers, one of them has 16 colors on the tile
8-color palettes, the second - 256 without palettes.
The most complex mode is MODE7,
provides a 256-color layer
the possibility of its rotation, and scaling
of.

   There interrupt VBLANK and skanlaynu.
If you exceed the limit of sprites on skanlayn
(Unlike other VDP, a SNES restrictive
is called the number of pixels, rather than themselves
Sprites), the first missing neighbors valid
you if there is overlapping. There svoeob
different hardware effects 'pixelation', not
very nice-looking, but often encountered
waiting for a game (when changing the screen) - iso
map smoothly transformed into a set of cumbersome
madnyh pixels. Continuing the practice started
thuja NES, the possibility of attachment can change
propagate in dependence on an additional
paratury on the cartridge - including prodvinu
Tide video modes (from small improvements
existing regimes to special processor for
O textured and lit triangles
golnikov in 3D-games). Such expansion
quite extensively used in games.


       Brief Specifications V9990


   Now consider the possibility of closer
V9990, to understand what it represents
themselves, and how his chances are better or
worse than the platformers VDP.

   V9990 is a senior in the lineup of chips
TMS9918/9928/9929 (MSX1), V9938 (MSX2),
V9958 (MSX2 +, TurboR). It is based on
ideas V9958, but backward compatibility
between these chips net.Polnoe name chip
- Yamaha E-VDP-III V9990.Kak all VDP for
MSX, it is not purely 'platformers'.
Yamaha has positioned it as a solution for
use in video games, multimedia systems
Themes and industrial automation. The chip has
as a block mode with hardware sprite
mi and bitmap, with the possibility of machine
Nogo perform the rendering for
mitivov and transfer blocks of graphics. In ka
Unpack the kettle output devices supported by them
not only the conventional TV, but also a VGA-Monitor
and LCD-panel.

   For video game applications predusmot
Reno two block video mode: P1 with a resolution
sheniem 256x212 and P2 with a resolution of 512x212.
While P1 is supported by two layers of background,
in P2 - a single layer. The background is made up of blocks
Cove 8x8 points. 16 colors on the block, 4 panel
of 16 colors defined in the 15-bit color.
Number of image blocks - 8160 7680
for P1, 15360 for P2. Buffer size of the background -
64x64 block mode P1 (for each
layer) and 128x64 mode P2. There's apparatus
tnye sprites. The simultaneous mapping
expression 125 sprites on the screen, and up to 16
sprites on the same horizontal line.
Sprites have a size of 16x16 pixels, 16 CEE
Comrade a sprite and 4 palitry.V videopamya
Tee, you can store up to 256 images Handbook
Comrade. There is a system of priorities map
tween layers and sprites: priority
between the layers of background and sprite is given each
home in person, the order of valid
ytov determined by serial nomerom.Obschee
the number of colors simultaneously displayed on
screen in these modes, equal to 64 (from a palette
at 32,768).

   Raster video modes are presented in
large numbers: it's modes B0-B7. They
different resolutions - from 192x240 to
1024x424 (some permits available
Only for VGA), the number of displayed
flowers (4 ... 32 768) and methods of their representation
resistivity (RGB, YJK, YUV, etc.), size
image buffer - from 512x512 to 1024x
x2048. In these modes available hardware
display two cursors, and 32x32
points in 3 colors. In the operations of the hardware
transfer blocks of data (processor / video
memory, video memory, video memory, videopa
rumple-processor) and drawing primitives
(Point, line, monochrome print on a mission
colors) you can specify different logical
Kie operations performed on the data.

   Among the other features present
program centering the image on the screen
not, imposing image to an external video
signal (using a special bit in the value
chenii color indicates an external display
tions signal or the desired point of videopamya
ty). There are interruptions to achieve beam
the desired point of the raster (given its coordinates
you, and you can choose - repeat interruption
on each line, or only on specified
Noah), the VSYNC, on completion of the
team. Possible to connect video
volume from 128 to 512 kilobytes.

Shiru