PLSCMAP1LA(3plplot)

💅 NAME 💅

okay so, bestie, this is plscmap1la — from the 3plplot manual — and it's the one that sets cmap1 colors AND alpha transparency using a piece-wise linear relationship. yes, both. she does it all. ✨

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🎀 SYNOPSIS 🎀

plscmap1la(itype, npts, intensity, coord1, coord2, coord3, alpha,
alt_hue_path)

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🌈 DESCRIPTION 🌈

So this is the glow-up variant of plscmap1l(3plplot) — literally the same energy, except she supports alpha channel transparency. iconic behavior only. 💅

What she does: she sets cmap1 colors using a piece-wise linear relationship between the cmap1 intensity index (0.0-1.0) and position in HLS or RGB color space (peep the PLplot documentation for that part, iykyk) — plus an alpha transparency value (0.0-1.0). 🦋

And the best part? It may be called at any time. no timing restrictions, no waiting for the right moment, she's always available. main character energy fr fr. 👑

Redacted form: plscmap1la(itype, intensity, coord1, coord2, coord3, alpha, alt_hue_path) — yes, npts dips out of the redacted version, that's just how it is, no cap. 🙈

Oh and also — this function is used in example 30. go look, it's cute. 💖

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✨ ARGUMENTS ✨

• itype (PLBOOL(3plplot), input) — the classic binary baddie: true means RGB, false means HLS. pick your color space, bestie. 🎨
• npts (PLINT(3plplot), input) — number of control points. that's it. that's the count. 🔢
• intensity (PLFLT_VECTOR(3plplot), input) — a vector holding the cmap1 intensity index (0.0-1.0) for each control point, and it's gotta be in ascending order. do not come in here all chaotic and unsorted. ⬆️
• coord1 (PLFLT_VECTOR(3plplot), input) — a vector with the first coordinate (either H or R, depending on your itype situation) for each control point. 🌸
• coord2 (PLFLT_VECTOR(3plplot), input) — a vector with the second coordinate (either L or G) for each control point. 🍓
• coord3 (PLFLT_VECTOR(3plplot), input) — a vector with the third coordinate (either S or B) for each control point. 💜
• alpha (PLFLT_VECTOR(3plplot), input) — a vector with the alpha transparency value (0.0-1.0) for each control point. this is literally her whole thing, the transparency, the see-through-ness, the vibe. 🫶
• alt_hue_path (PLBOOL_VECTOR(3plplot), input) — a vector (with npts - 1 elements, note the minus one!!) holding the alternative interpolation method Boolean value for each control point interval. and before you ask — yes, alt_hue_path[i] refers to the interpolation interval between the i and i + 1 control points. so it's intervals, not points. write that down. 📝

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👑 AUTHORS 👑

Many developers have contributed to PLplot over its long history — and they're all credited at http://plplot.sourceforge.net/credits.php. legends, every single one of them. 🏆

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🔥 SEE ALSO 🔥

PLplot documentation at http://plplot.sourceforge.net/documentation.php. go read, it's giving educational. 📚

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mwah 💋 that's the whole page, bestie — PLplot API, 3plplot, dated August, 2026 (future girl summer fr fr). now go make something transparent and gorgeous. 🧚✨