MMA_Video_DestOffsetX
MMA_Video_DestOffsetX (V50) [ISGPQ], ULONG
DESCRIPTION
Specifies horizontal offset of upper-left corner of displayed image
relative to the rastport origin. The default value is zero, so image
is aligned to the rastport left edge
SEE ALSO
MMA_Video_DestOffsetY
MMA_Video_DestOffsetY (V50) [ISGPQ], ULONG
DESCRIPTION
Specifies vertical offset of upper-left corner of displayed image
relative to the rastport origin. The default value is zero, so image
is aligned to the rastport top edge
SEE ALSO
MMA_Video_FinalTouch
MMA_Video_FinalTouch (V50) [..G..], BOOL
DESCRIPTION
The attribute is used when displaying a progressive display. When
MMM_Play is called on progressive data, picture.output object fetches
first progressive aproximation of the image, displays it and returns.
Then application calls MMM_Play in a loop until MMA_Video_FinalTouch
gets TRUE, it means the last MMM_Play call has displayed the image in
its final, most precise version
NOTES
If source has no progressive display data, or progressive display is
switched off, this attribute is TRUE after the first MMM_Play call.
SEE ALSO
MMA_Video_GlobalAlpha
MMA_Video_GlobalAlpha (V50) [ISGPQ], ULONG
DESCRIPTION
Global alpha value is a constant which every pixel alpha value is
premultiplied by. It may be used regardless of original alpha channel
presence. Ranges from $FF (full opacity) to 0 (maximum
transparency). Let's look at examples:
Pixel alpha Global alpha Result
$00 $00 $00 (maximum transparency)
$FF $FF $FF (full opacity)
$00 $FF $FF (maximum transparency)
$FF $00 $FF (maximum transparency)
$7F (1/2) $00 $00 (maximum transparency)
$7F (1/2) $7F (1/2) $3F (1/4 opacity)
$7F (1/2) $FF $7F (1/2 opacity)
The default value is 255 ($FF), fully opaque image
SEE ALSO
MMA_Video_Height
MMA_Video_Height (V50) [..G..], ULONG
DESCRIPTION
Specifies the height of displayed frame
SEE ALSO
MMA_VideoWidth
MMA_Video_Progressive
MMA_Video_Progressive (V50) [ISGPQ], BOOL
DESCRIPTION
When set [ISP], controls if the class uses progressive display
information contained in the source data. TRUE means progressive
display is in use. FALSE causes ignoring this information, also the
attribute is propagated back through the pipeline to inform all
objects to skip/ignore progressive display data as well. When get
[GQ], is TRUE if sorce data contain progressive display data AND
it is used for display. The default value for this tag is FALSE, so
proggresive display data are ignored
NOTES
This attribute has meaning only for pictures, frames of video streams
do not have progressivity usually.
SEE ALSO
MMA_Video_RastPort
MMA_Video_RastPort (V50) [ISGPQ], struct RastPort*
DESCRIPTION
Specifies destination rastport. NULL value switches output off.
Specified rastport is checked against palettized bitmap, so
specifying such rastport is safe in terms of stability, but of course
no output will be rendered. Default value is NULL (no output
MMA_Video_UseAlpha
MMA_Video_UseAlpha (V50) [ISGPQ], BOOL
DESCRIPTION
Controls usage of alpha channel data in the source stream. If FALSE
alpha channel is ignored (all pixels are assumed to be opaque). This
is independent of MMA_Video_GlobalAlpha, so for example image alpha
channel can be switched off and then global alpha applied. The default
value is MMA_Video_UseAlpha read from input port. It is TRUE if source
stream contains alpha channel, FALSE otherwise
NOTES
Forcing alpha usage on images not having alpha channel data is
useless as it only slows blitting down and does not change the result
at all.
SEE ALSO
MMA_Video_Width
MMA_Video_Width (V50) [..G..], ULONG
DESCRIPTION
Returns the width of displayed frame
SEE ALSO
MMA_VideoHeight
MMM_Play
MMM_Play (V50)
SYNOPSIS
DoMethod(obj, MMM_Play);
DESCRIPTION
Renders the picture at specified position in the rastport. Data are
fetched from the pipeline and blitted. Big images are blitted in
strips to lower memory usage. Maximum single strip size is 128 kB.
If MMM_Play is called on progressive data, picture.output object
fetches first progressive aproximation of the image, displays it and
returns. Then application calls MMM_Play in a loop until
MMA_Video_FinalTouch gets TRUE, it means the last MMM_Play call has
displayed the image in its final, most precise version
SEE ALSO
background
DESCRIPTION
Picture.output is a Reggae data output class. The class is designed
for rendering image media stream into a RastPort. The RastPort must
be hi/truecolor (palettized rastports are not supported). Class
features are:
- destination offset is supported via MMA_Video_DestOffsetX and
MMA_Video_DestOffsetY attributes.
- picture.output has no internal clipping. On layered rastports (all
window and screen rastports are layered) you can rely on layer
clipping. On non-layered, typically off-screen rastports, clipping
must be done by application.
- alpha channel (transparency) support.
- global alpha (transparency) value independent of image alpha
channel. It means global alpha may be applied to image not having
alpha channel.
The class is a direct subclass of multimedia.class.
NEW ATTRIBUTES
Attributes applicability:
I - may be set at creation time.
S - may be set on an existing object.
G - may be get from an object.
P - may be set for an object's port.
Q - may be queried from an object's port.
MMA_Video_DestOffsetX (V50) [ISGPQ], ULONG
MMA_Video_DestOffsetY (V50) [ISGPQ], ULONG
MMA_Video_FinalTouch (V50) [..G..], BOOL
MMA_Video_GlobalAlpha (V50) [ISGPQ], ULONG
MMA_Video_Height (V50) [..G..], ULONG
MMA_Video_Progressive (V50) [ISGPQ], BOOL
MMA_Video_RastPort (V50) [ISGPQ], struct RastPort*
MMA_Video_UseAlpha (V50) [ISGPQ], BOOL
MMA_Video_Width (V50) [..G..], ULONG
NEW METHODS
MMM_Play() (V50)