go-p5/p5

p5 is a simple package that provides primitives resembling the ones exposed by p5js.org

p5's Issues

KeyPress event absent

gio: sw renderer hiccups

with Gio>=v0.0.0-20210729070555-8cec7e04eb71 there appears to be a slight graphical hiccups when comparing an image produced with or w/o the libGL s/w renderer (the GitHubActions CI test on Linux falls back on using libGL s/w renderer.)

• image with GPU backend:
  

• image with s/w renderer:
  

see:

• 82e90d6

p5: implement FrameCount()

reference: https://p5js.org/reference/#/p5/frameCount

p5: expose a way to record animations

• saveFrames

https://p5js.org/reference/#/p5/saveFrames

is custom font supported?

I looked for it in the documentation but it's not there so I guess not

Tests are fragile due to image comparison

I am trying to run locally the test suite but it fails due to existing delta of 0.05

=== RUN TestAPIShapes
api_test.go:61: testdata/api_shapes.png: images compare different
--- FAIL: TestAPIShapes (0.08s)

Increasing delta to 0.06 make test green.

Is there any other more robust way to implement tests avoiding image comparison completely? Is there a way to compare the state that produces the images instead of the images themselves?

p5: implement more of p5js API

we should implement more of the p5js API:

• https://p5js.org/reference/

• path

• rotate

• scale

• transform

• push/pop

• bézier

• curve

• frame-rate

• resize-canvas

• vector (just use gonum.org/v1/gonum/spatial/r2.Vec)

• image loading, image display

• keyboard callbacks

math

• noise (https://p5js.org/reference/#/p5/noise)
• noiseDetail (https://p5js.org/reference/#/p5/noiseDetail)
• noiseSeed (https://p5js.org/reference/#/p5/noiseSeed)

p5: retain state from draw-to-draw

in Processing and in p5js, the state of the display is retained from iteration to iteration.

right now, in p5, we don't (so, for example, in the mouse-pressed example, the circle around the mouse follows the mouse but doesn't leave a trail of circles across its path, as the p5js example does.)

that's actually a feature of Gio.

to "simulate" the same behaviour, we could have an image.Image field that is drawn to at the end of each draw cycle.
at cycle+1, we draw that last image.Image before invoking the user's draw function.

Entry on documentation outdated

There is an error on documentation on what a simple example using the library should look like, on line 20 the use of Square function has one argument more than it is required located on p5.go file:

    p5.Square(10, 10, 50, 50)

challenge screen

desc of what target is eg user per week

p5: rework event-loop drawing

right now, p5 relies on Gio to get its re-draw events, together with a little ticker goroutine (that ticks at the requested frequency, requesting Gio for redrawing the canvas).

it's a bit brittle because it's intertwined with other Gio events that will re-draw the canvas (such as a resize of the window), which will confuse users' draw methods (e.g.: the current solar-system draw methods expects a fixed frequency and computes delta-t (and thus positions, speeds and accelerations) from that frequency).

we'd need to somehow separate or distinguish the 2 sets of events. (probably by only re-drawing when the ticker goroutine marked some Proc state as "dirty"?)

Error trying to use p5.Rect

I am trying to use p5.Rect(382.732615, 14.503678, 52.000000, 73.000000), but it is returning the following error:
"not all path contours are closed"
Probably an skill issue, but can anybody help me?

p5: implement Loop(), NoLoop() and IsLooping()

https://p5js.org/reference/#/p5/loop
https://p5js.org/reference/#/p5/noLoop
https://p5js.org/reference/#/p5/isLooping

p5: send custom events in order to control the behavior of the draw loop

Currently the is no way to control the execution of Proc draw loop since it is handled by events received by a receive only channel (<-chan event.Event)

p5/proc.go

Line 208 in fea8ed5

e := <-w.Events()

).

Providing a way to send events and control/stop the loop would make Proc more testable.

Add Random(), RandomSeed() and RandomGaussian()

Add Random and RandomSeed methods, similar to https://p5js.org/reference/#/p5/random and https://p5js.org/reference/#/p5/randomSeed

Questions About specific stuff

I tried run p5 while doing other stuff like this:

basically, in this situation the p5 window doesnt run, there's a way to run it, while listening to connections?

I tried running it in concurrency mode:

but didnt worked.

The Second question is: How to Run it on browser using gorilla?

p5: add tests for shapes

p5: expose API to define physical dimensions

right now, p5.Proc takes a width and a height in pixels to set the canvas size.
but we should fine a way to map these dimensions to "physical" dimensions (ex: "U.A" or "km" for the solar system example) so users can just reason in their problem space.

internally, p5.Proc has already the logic to convert from "user" space coordinates to "system" coordinates.

Requesting update for Gioui changes to Stroke and Outline

Changes in calls to Outline and Stroke prevent go-p5 from compiling.
https://lists.sr.ht/~eliasnaur/gio-patches/patches/15848

p5: implement FrameRate()

https://p5js.org/reference/#/p5/frameRate

Currently the is no way to override the default ticker, so there is no way to change the frame rate.

One solution would be to reset the ticker using https://golang.org/pkg/time/#Ticker.Reset whenever there is an update to Proc.ctl.FrameRate().