diff --git a/CHANGELOG.md b/CHANGELOG.md --- a/CHANGELOG.md +++ b/CHANGELOG.md @@ -1,5 +1,9 @@ # Revision history for granite +## 0.7.1.0 -- 2026-05-25 + +* Numeric `aesAlpha` mappings are now honoured for points (per-point opacity); previously only the per-layer `defAlpha` was applied. + ## 0.7.0.0 -- 2026-05-24 * `Color` is now a 24-bit RGB value, and categorical colour mappings are honoured for points. diff --git a/granite.cabal b/granite.cabal --- a/granite.cabal +++ b/granite.cabal @@ -1,6 +1,6 @@ cabal-version: 3.0 name: granite -version: 0.7.0.0 +version: 0.7.1.0 synopsis: Easy terminal plotting. description: A terminal plotting library for quick and easy visualisation. license: MIT diff --git a/src/Granite/Render/Pipeline.hs b/src/Granite/Render/Pipeline.hs --- a/src/Granite/Render/Pipeline.hs +++ b/src/Granite/Render/Pipeline.hs @@ -440,8 +440,16 @@ | Just cats <- categoricalColorColumn frame m -> map (\cat -> specToColor (fromMaybe colorSpec (lookup cat levelColors))) cats _ -> repeat col + pointAlphas = case resolveNumColumn frame (aesAlpha m) of + Just vs@(_ : _) -> + let lo = minimum vs + hi = maximum vs + in if hi <= lo + then repeat alpha + else map (\v -> 0.15 + 0.85 * (v - lo) / (hi - lo)) vs + _ -> repeat alpha in case layerGeom layer of - GeomPoint -> drawPoints proj frame m pointColors radius alpha + GeomPoint -> drawPoints proj frame m pointColors radius pointAlphas GeomLine -> drawLine proj frame m colorSpec lineW GeomBar -> drawBars proj frame m col GeomCol -> drawBars proj frame m col @@ -460,9 +468,9 @@ Mapping -> [Color] -> Double -> - Double -> + [Double] -> [Mark] -drawPoints proj frame m cols r alpha = +drawPoints proj frame m cols r alphas = case (resolveNumColumn frame (aesX m), resolveNumColumn frame (aesY m)) of (Just xv, Just yv) -> [ MCircle @@ -470,9 +478,9 @@ r defaultStyle { styleFill = Just c - , styleFillOpacity = alpha + , styleFillOpacity = a } - | ((x, y), c) <- zip (zip xv yv) cols + | ((x, y), c, a) <- zip3 (zip xv yv) cols alphas ] _ -> [] diff --git a/test/GoldenSpec.hs b/test/GoldenSpec.hs --- a/test/GoldenSpec.hs +++ b/test/GoldenSpec.hs @@ -63,6 +63,32 @@ ] (Just "Random points") +-- A scatter whose point opacity is driven by a numeric column via 'aesAlpha': +-- low weight -> faint, high weight -> opaque. Locks in per-point alpha. +alphaScatter :: Chart +alphaScatter = + let df = + fromColumns + [ ("x", ColNum [0, 1, 2, 3, 4]) + , ("y", ColNum [0, 1, 2, 3, 4]) + , ("w", ColNum [1, 2, 3, 4, 5]) + ] + layer = + (defLayer GeomPoint) + { layerMapping = + emptyMapping + { aesX = Just (ColumnRef "x") + , aesY = Just (ColumnRef "y") + , aesAlpha = Just (ColumnRef "w") + } + } + in emptyChart + { chartData = df + , chartLayers = [layer] + , chartTitle = Just "Alpha by weight" + , chartSize = SizeChars 40 14 + } + singleSeriesLine :: Chart singleSeriesLine = lineChart @@ -295,6 +321,9 @@ it "no-title scatter renders to expected SVG output" $ goldenText "scatter-no-title.svg" (renderChartSvg noTitleScatter) + + it "alpha-mapped scatter renders to expected SVG output" $ + goldenText "scatter-alpha.svg" (renderChartSvg alphaScatter) describe "Line chart" $ do it "single-series line renders to expected terminal output" $ diff --git a/test/golden/scatter-alpha.svg b/test/golden/scatter-alpha.svg new file mode 100644 --- /dev/null +++ b/test/golden/scatter-alpha.svg @@ -0,0 +1,23 @@ + + + + +0.0 +1.0 +2.0 +3.0 +4.0 +0.0 +1.0 +2.0 +3.0 +4.0 + + + + + +Alpha by weight + +series 0 +