Improve histogram for legend optimization

[AHammerLine]

Description

NightVision is a great library, I enjoy the most of its fetures. However, there is some minor flaw yet.

I use histogram overlay to chart my indicator, named pc3 in second pane. The indicator doesn't need extra moving average, so I don't put the data of value and signal in overlay. The problem is that legend title still presents two "x" even without data, see my fig below.

I know the histogram overlay is designed for MACD, but it would be nicer with more flexibility.

Appriciating for your attentions.

Suggested solution

Add a propery Histogram.showLine in Overlay object likes candles do. And program checks the value, if true then charts line and displays value on legend, otherwise, doesn't show it.

Alternative

No response

Additional context

No response

Validations

• Read the docs.
• Check that there isn't already an issue that request the same feature to avoid creating a duplicate.

[C451]

We have even better one: just copy the .navy file, replace the name [OVERLAY name=PC3... and change the legend function.

[AHammerLine]

Thanks, I have read the navy docs, that's a gread idea, but I sitll have a question here. My indicator need antoher data except ohlcv for calculation, say, "amount", how could I introduce the data into navy script?

[C451]

For now it's the props field, later will also be dataStatic

[AHammerLine]

For now it's the props field, later will also be dataStatic

What data format supposed? I past like [<timestamp>, value], but it didn't work。

"scripts": [
...
"props": {
    "data": [
    [1648360800000, 13.92],
    [1648364400000, 14.92]
]
}
]

[C451]

Try to add in your overlay :

prop('data', { type: 'array', def: [] })

Then:

$props.data

[AHammerLine]

Try to add in your overlay :

prop('data', { type: 'array', def: [] })

Then:

$props.data

Oh, I see. What if I want to custom an indicator script? Suppose I custom a TEST indicator to compute some data and draw by Spline overlay, how should I specific the data format that could be recognized and handled properly? I try below these, but doesn't work.

// App.svelte
chart = new NightVision("chart-container", {
            data: dataShort,
            scripts: [
                `
[Overlay name=TEST, versiont=1.0.0]

prop('data', { type: 'array', def: [] })

[UPDATE]

let data = ts($props.data, [])
console.log(data)
Spline(data, {
    name: "test"
})

`,
            ],
        });

and dataShort is imported by a json file:

// dataShort.json
{
    "panes": [
        {
            "overlays": [
                {
                    "name": "APE / Tether US",
                    "type": "Candles",
                    "main": true,
                    "data": [
                        [
                            1648360800000,
                            13.92,
                            14.083,
                            13.5025,
                            13.92,
                            10379666.97
                        ],
                        [
                            1648364400000,
                            13.92,
                            14.2455,
                            13.871,
                            14.157,
                            19149600.5
                        ],
                        [
                            1648368000000,
                            14.157,
                            14.3755,
                            14.013,
                            14.2695,
                            12874309.69
                        ],
                        [
                            1648371600000,
                            14.2695,
                            14.2695,
                            13.9535,
                            13.9645,
                            8899211.04
                        ],
                        [
                            1648375200000,
                            13.9645,
                            14.076,
                            13.8415,
                            13.8525,
                            13092402.18
                        ],
                        [
                            1648378800000,
                            13.8525,
                            14.029,
                            13.7325,
                            13.987,
                            9720198.64
                        ],
                        [
                            1648382400000,
                            13.987,
                            14.05,
                            13.74,
                            13.74,
                            9190532.1
                        ],
                        [
                            1648386000000,
                            13.74,
                            14,
                            13.56,
                            13.948,
                            12672318.36
                        ],
                        [
                            1648389600000,
                            13.948,
                            14.04,
                            13.81,
                            13.838,
                            6286435.6
                        ],
                        [
                            1648393200000,
                            13.838,
                            14.17,
                            13.781,
                            13.9485,
                            7569704.26
                        ]
                    ],
                    "settings": {},
                    "props": {}
                }
            ]
        },
        {
            "scripts": [
                {
                    "type": "TEST",
                    "props": {
                        "data": [
                                4,
                                5,
                                9,
                                4,
                                1,
                                6,
                                1,
                                3,
                                6,
                                2
                        ]
                    }
                }
            ]
        }
    ]
}

[C451]

You need scripts to produce new data, overlays for rendering (by design).

[AHammerLine]

You need scripts to produce new data, overlays for rendering (by design).

I know ... but how can I pass additional data except ohlcv to an indicator script, for illustration, suppose I download turnover data which cannot be produced by ohlcv , how could I use them as close do in ema(close, 12). Close is stored in a ScriptEngine object, how could I tell ScriptEngine to save my turnover data?