Hi Josh, I have addressed the same in my code right now. The code compiles and throws no errors now. This is the version that we have now: https://github.com/JHBalaji/media/blob/master/audio/src/param.rs#L419-L433
Can you please see if this is fine? Also, we have a submission for this assignment on Monday so can we submit a pull request with what we have till now? Also, we will continue to work on Mozilla for our final semester project and considering that we have a better hang of how WebAudio works I think we can actively contribute. Thanks again for your valuable inputs, we are now able to understand the flow of code much better. - Akhilesh On Sat, Mar 30, 2019 at 12:27 AM Josh Bowman-Matthews <j...@joshmatthews.net> wrote: > Answers inline: > > On 3/29/19 7:54 PM, Akhilesh Venkatasubramanian wrote: > > Hi Josh, > > > > We went ahead to try to implement the function and are facing some issues > > and your insight will be helpful. > > > > 1. We have implemented the function here: > > > > > https://github.com/JHBalaji/media/blob/master/audio/src/param.rs#L419-L434 > > < > https://github.com/JHBalaji/media/blob/master/audio/src/param.rs#L419-L434 > >. > > > > A) Can you check if our implementation of interpolating between v[k] > and > > v[k+1] is correct? If not, can you give us a heads up as to how to > > proceed? > > It took me a while to step through it and convince myself that it made > sense, but I think it's right. I'll probably ask one of our Web Audio > experts to double-check it. The naming of x1/x2 and y1/y2 did not help > me; I would suggest using names like v_k and v_k_next as well as time_k > and time_k_next to improve readability. > > > > The above code does give out a few errors as below: > > > > Compiling servo-media-audio v0.1.0 > (/Users/akhilesh/Desktop/media/audio) > > > > error[E0277]: cannot subtract `block::Tick` from `f32` > > > > --> audio/src/param.rs:432:37 > > > > | > > > > 432 | *value = (y1 * (x2 - current_tick) + y2 * > > (current_tick - x1)) / (x2 - x1) as f32; > > > > | ^ no implementation for `f32 - > > block::Tick` > > > > | > > > > = help: the trait `std::ops::Sub<block::Tick>` is not implemented > for > > `f32` > > > > > > error[E0277]: cannot subtract `f32` from `block::Tick` > > > > --> audio/src/param.rs:432:74 > > > > | > > > > 432 | *value = (y1 * (x2 - current_tick) + y2 * > > (current_tick - x1)) / (x2 - x1) as f32; > > > > | > > ^ no implementation for `block::Tick - f32` > > > > | > > > > = help: the trait `std::ops::Sub<f32>` is not implemented for > > `block::Tick` > > > > > > error: aborting due to 2 previous errors > > > > I was not able to subtract current_tick from the value instance I > generated > > to keep track of the expected time for v[k] and v[k+1]. Can you give me > > some pointers as to how I can fix the same? > > You can find the documentation for block::Tick at > https://doc.servo.org/servo_media_audio/block/struct.Tick.html . If you > click the "Show Declaration", you will see that it wraps a u64 value, > which you can retrieve with `current_tick.0` and can then cast to f32. > > > > > > > > B) Should we declare the values vector and duration also somewhere else > in > > the program or are the changes made by me enough to handle the function? > > > > 2. There was one more modification I had to make to make the code compile > > till the previous point. In L259 > > <https://github.com/JHBalaji/media/blob/master/audio/src/param.rs#L259> > and > > L271, if I also had the Copy trait called then it shows the error posted > > below, which I believe is because of the values vector in the > > SetValueCurveAtTime function. Can I just remove the copy trait or is > there > > any other modification that I have to make? > > > > error[E0204]: the trait `Copy` may not be implemented for this type > > > > --> audio/src/param.rs:259:17 > > > > | > > > > 259 | #[derive(Clone, Copy, PartialEq, Debug)] > > > > | ^^^^ > > > > ... > > > > 266 | SetValueCurveAtTime(Vec<f32>, Tick, /* duration */ f64), > > > > | -------- this field does not implement > `Copy` > > > > > > error[E0204]: the trait `Copy` may not be implemented for this type > > > > --> audio/src/param.rs:271:17 > > > > | > > > > 271 | #[derive(Clone, Copy, PartialEq, Debug)] > > > > | ^^^^ > > > > ... > > > > 278 | SetValueCurveAtTime(Vec<f32>, f64, /* duration */ f64), > > > > | -------- this field does not implement > `Copy` > > > > > > error: aborting due to 2 previous errors > > > > > > For more information about this error, try `rustc --explain E0204`. > > > > error: Could not compile `servo-media-audio`. > > > > This was apparently a problem for the group which worked with the > > Oscillator node last semester and they weren't able to implement the > custom > > method > > < > https://github.com/servo/media/blob/master/audio/src/oscillator_node.rs#L150 > > > > because they weren't able to solve this issue and when I spoke to one > > person he said that removing the copy trait started showing up more > errors > > later. Can you give us your take on this? > > Removing the Copy trait is fine. Any code that relies on it can have an > explicit `.clone()` added to it and it should compile. > > Cheers, > Josh > _______________________________________________ > dev-servo mailing list > dev-servo@lists.mozilla.org > https://lists.mozilla.org/listinfo/dev-servo > _______________________________________________ dev-servo mailing list dev-servo@lists.mozilla.org https://lists.mozilla.org/listinfo/dev-servo
