Expose the information in the ImageData type. #28
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- Getting width and height of an ImageData are not effecting. - The pixel information is availalbe as a Uint8ClampedArray.
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| -- | An array of pixel data. | ||
| foreign import data CanvasPixelArray :: * | ||
| type ImageData = { width :: Number, height :: Number, data :: Uint8ClampedArray } |
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This is much nicer than a foreign type 😄
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I haven't worked with the FFI before. The underlying value the canvas gives us will be a Number with an integral value. If I can just declare it as Int here and that works, that's great. If I need to explicitly call fromNumber on it inside the js function I'm happy to do that too.
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The docs say height is "an unsigned long representing the actual height" for example. I think we can use Int here.
The reason for the current code is that Number was the only option back when this was added.
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Is the underlying representation of Int still just a Number? I'm not sure whether I can just declare the type here and it works or if I need to actually coerce the Number to an Int.
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Yep, it's just a number. They're syntactically forced to be actual ints in the compiler, and the operators are modified to preserve integerness.
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Looks nice! I'm happy to make a major version release since the type changes make things much simpler IMO. |
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Alright, updated those to |
| @@ -23,6 +23,7 @@ | |||
| "purescript-eff": "^0.1.0", | |||
| "purescript-functions": "^0.1.0", | |||
| "purescript-maybe": "^0.3.0", | |||
| "purescript-exceptions": "^0.3.1" | |||
| "purescript-exceptions": "^0.3.1", | |||
| "purescript-arraybugger-types": "^0.2.0" | |||
This is what I get for testing my changes by copy/pasting into an existing bower_modules/ folder. Sorry
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Ugh. So, learning opportunity: what is the right way to actually try the local changes in a library like this that isn't runnable itself? I was literally copy/pasting changes into another instance of purescript-canvas inside the bower-modules of a project I was building. But that obviously doesn't cover problems like this. |
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We can add a |
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Ok I can confirm that was failing before the spelling change and passes On Wed, Dec 16, 2015 at 9:26 PM, Phil Freeman [email protected]
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Expose the information in the ImageData type.
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Thanks! |
This is my first contribution to a purescript module in public use, so let me know if I've done something wrong. In particular, I've removed some signatures that could be backwards-compatibly implemented, but would perhaps be confusing in the future. I don't know how this community thinks about changing contracts in releases so I am happy to put them back.