Fix broken SVGs by not using `Cairo.pattern_set_extend(p, Cairo.EXTEN…

…D_PAD)` (#3967)

* Fix broken SVGs by not using `Cairo.pattern_set_extend(p, Cairo.EXTEND_PAD)`

* add changelog

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Changelog
 
 ## [Unreleased]
+- CairoMakie: Fix broken SVGs when using non-interpolated image primitives, for example Colorbars, with recent Cairo versions [#3967](https://github.com/MakieOrg/Makie.jl/pull/3967).
 - CairoMakie: Add argument `pdf_version` to restrict the PDF version when saving a figure as a PDF [#3845](https://github.com/MakieOrg/Makie.jl/pull/3845).
 - CairoMakie: Fix incorrect scaling factor for SVGs with Cairo_jll 1.18 [#3964](https://github.com/MakieOrg/Makie.jl/pull/3964).
 

CairoMakie/src/infrastructure.jl

@@ -143,7 +143,7 @@ end
 #   instead of the whole Scene
 # - Recognize when a screen is an image surface, and set scale to render the plot
 #   at the scale of the device pixel
-function draw_plot_as_image(scene::Scene, screen::Screen, primitive::Plot, scale::Number = 1)
+function draw_plot_as_image(scene::Scene, screen::Screen{RT}, primitive::Plot, scale::Number = 1) where RT
     # you can provide `p.rasterize = scale::Int` or `p.rasterize = true`, both of which are numbers
 
     # Extract scene width in device indepentent units
@@ -163,8 +163,11 @@ function draw_plot_as_image(scene::Scene, screen::Screen, primitive::Plot, scale
     # Cairo.scale(screen.context, w / scr.surface.width, h / scr.surface.height)
     Cairo.set_source_surface(screen.context, scr.surface, 0, 0)
     p = Cairo.get_source(scr.context)
-    # this is needed to avoid blurry edges
-    Cairo.pattern_set_extend(p, Cairo.EXTEND_PAD)
+    if RT !== SVG
+        # this is needed to avoid blurry edges in png renderings, however since Cairo 1.18 this
+        # setting seems to create broken SVGs
+        Cairo.pattern_set_extend(p, Cairo.EXTEND_PAD)
+    end
     # Set filter doesn't work!?
     Cairo.pattern_set_filter(p, Cairo.FILTER_BILINEAR)
     Cairo.fill(screen.context)

CairoMakie/src/primitives.jl

@@ -782,7 +782,7 @@ premultiplied_rgba(a::AbstractArray{<:Color}) = RGBA.(a)
 premultiplied_rgba(r::RGBA) = RGBA(r.r * r.alpha, r.g * r.alpha, r.b * r.alpha, r.alpha)
 premultiplied_rgba(c::Colorant) = premultiplied_rgba(RGBA(c))
 
-function draw_atomic(scene::Scene, screen::Screen, @nospecialize(primitive::Union{Heatmap, Image}))
+function draw_atomic(scene::Scene, screen::Screen{RT}, @nospecialize(primitive::Union{Heatmap, Image})) where RT
     ctx = screen.context
     image = primitive[3][]
     xs, ys = primitive[1][], primitive[2][]
@@ -858,8 +858,11 @@ function draw_atomic(scene::Scene, screen::Screen, @nospecialize(primitive::Unio
         Cairo.scale(ctx, w / s.width, h / s.height)
         Cairo.set_source_surface(ctx, s, 0, 0)
         p = Cairo.get_source(ctx)
-        # this is needed to avoid blurry edges
-        Cairo.pattern_set_extend(p, Cairo.EXTEND_PAD)
+        if RT !== SVG
+            # this is needed to avoid blurry edges in png renderings, however since Cairo 1.18 this
+            # setting seems to create broken SVGs
+            Cairo.pattern_set_extend(p, Cairo.EXTEND_PAD)
+        end
         filt = interpolate ? Cairo.FILTER_BILINEAR : Cairo.FILTER_NEAREST
         Cairo.pattern_set_filter(p, filt)
         Cairo.fill(ctx)