Some SWFs report unreasonable bitmap dimensions, and trying to reserve
enough capacity for them always fails. To avoid panics, skip those bitmaps.
Fixes#1191Fixes#2759Fixes#10701
Previously, the MovieClip error state contained one TODO in order to be
completely implemented: The HeaderExt variable uncompressed_len needs to
be -1 in the error state, but its type has been u32.
The type has now been changed to i32, and the variable is set to -1 in
the default_error_header function. Therefore, the MovieClip error state
is now fully implemented.
Other connected functions and variables like SwfMovie::uncompressed_len
or MovieClip::total_bytes have been adjusted to this type change. Code
has been adjusted if needed where this value is used.
A load_error_swf function has been added to the Loader. It makes the
MovieClip enter the error state in which some attributes have certain
error values to signal that no valid file could be loaded. This happens
if no file could be loaded or if the loaded content is no valid
supported content.
The function creates an error state movie stub using the new
SwfMovie::error_movie function (which uses a new default_error_header
function) and configures remaining variables with the
movie_not_available method.
One TODO in order for the error state to be completely implemented has
been added.
Since the error state of the MovieClip includes the final URL of the SWF
file obtained after any redirects, the load_error_swf and
movie_loader_error functions (now) take an swf_url attribute.
To get this URL in case no file could be loaded, the
NavigatorBackend::fetch method has been changed to return an
ErrorResponse struct (including the url and the actual error) in the
error case. The Response struct returned in the success case has been
renamed to SuccessResponse.
All fetch implementations have been adapted accordingly. Code has been
adjusted to return the actual error where that's needed.
Documentation has been added and improved.
Generally, when transforming a difference between two points, `p1`
and `p2`, with a matrix `m`, we would like the following property
to hold:
```
m * (p1 - p2) == m * p1 - m * p2
```
Unfortunately, it wasn't like this before, because matrices have a
translation component, which is non-linear. In `m * p1 - m * p2`,
the translations of `m * p1` and `m * p2` are the same and therefore
cancel out each other. However, in `m * (p1 - p2)` the translation
stays.
In order to preserve this property, introduce a new `PointDelta`
type which is not subject to translation when transformed by a matrix.
For now, the following operations are supported:
* `Point - Point -> PointDelta`
* `Point + PointDelta -> Point`
* `Point += PointDelta`
* `Point - PointDelta -> Point`
* `Point -= PointDelta`
As a consequence, the expression `position + global_to_local_matrix * mouse_delta`
in `update_drag()` now ignores translation, which fixes#817.
Tom Schuster