slider linewidth controls autosize, correct vertical

src/makielayout/defaultattributes.jl

@@ -504,9 +504,9 @@ function default_attributes(::Type{LSlider}, scene)
         "The vertical alignment of the slider in its suggested bounding box."
         valign = :center
         "The width setting of the slider."
-        width = nothing
+        width = Auto()
         "The height setting of the slider."
-        height = 15
+        height = Auto()
         "The range of values that the slider can pick from."
         range = 0:10
         "Controls if the parent layout can adjust to this element's width"
@@ -517,6 +517,8 @@ function default_attributes(::Type{LSlider}, scene)
         startvalue = 0
         "The current value of the slider."
         value = 0
+        "The width of the slider line"
+        linewidth = 15
         "The color of the slider when the mouse hovers over it."
         color_active_dimmed = COLOR_ACCENT_DIMMED[]
         "The color of the slider when the mouse clicks and drags the slider."

src/makielayout/lobjects/lslider.jl

@@ -7,7 +7,7 @@ function LSlider(parent::Scene; bbox = nothing, kwargs...)
     decorations = Dict{Symbol, Any}()
 
     @extract attrs (
-        halign, valign, horizontal,
+        halign, valign, horizontal, linewidth,
         startvalue, value, color_active, color_active_dimmed, color_inactive
     )
 
@@ -17,6 +17,14 @@ function LSlider(parent::Scene; bbox = nothing, kwargs...)
     layoutobservables = LayoutObservables{LSlider}(attrs.width, attrs.height, attrs.tellwidth, attrs.tellheight,
         halign, valign, attrs.alignmode; suggestedbbox = bbox, protrusions = protrusions)
 
+    onany(linewidth, horizontal) do lw, horizontal
+        if horizontal
+            layoutobservables.autosize[] = (nothing, Float32(lw))
+        else
+            layoutobservables.autosize[] = (Float32(lw), nothing)
+        end
+    end
+
     sliderbox = lift(identity, layoutobservables.computedbbox)
 
     endpoints = lift(sliderbox, horizontal) do bb, horizontal
@@ -31,7 +39,7 @@ function LSlider(parent::Scene; bbox = nothing, kwargs...)
         else
             x = left(bb) + w / 2
             [Point2f0(x, bottom(bb) + w/2),
-             Point2f0(x, top(bb) + h/2)]
+             Point2f0(x, top(bb) - w/2)]
         end
     end
 
@@ -80,10 +88,6 @@ function LSlider(parent::Scene; bbox = nothing, kwargs...)
         [ca, ci]
     end
 
-    linewidth = lift(horizontal, sliderbox) do hori, sbox
-        hori ? height(sbox) : width(sbox)
-    end
-
     endbuttons = scatter!(parent, endpoints, color = linecolors, markersize = linewidth, strokewidth = 0, raw = true)[end]
     decorations[:endbuttons] = endbuttons
 
@@ -146,8 +150,8 @@ function LSlider(parent::Scene; bbox = nothing, kwargs...)
         linecolors[] = [color_active_dimmed[], color_inactive[]]
     end
 
-    # trigger bbox
-    layoutobservables.suggestedbbox[] = layoutobservables.suggestedbbox[]
+    # trigger autosize through linewidth for first layout
+    linewidth[] = linewidth[]
 
     LSlider(parent, layoutobservables, attrs, decorations)
 end