Support for rendering image markers with CairoMakie

CairoMakie/src/primitives.jl

@@ -204,10 +204,12 @@ end
 # an array of markers is converted to string by itself, which is inconvenient for the iteration logic
 _marker_convert(markers::AbstractArray) = map(m -> convert_attribute(m, key"marker"(), key"scatter"()), markers)
 _marker_convert(marker) = convert_attribute(marker, key"marker"(), key"scatter"())
+# image arrays need to be converted as a whole
+_marker_convert(marker::AbstractMatrix{<:Colorant}) = [ convert_attribute(marker, key"marker"(), key"scatter"()) ]
 
 function draw_atomic_scatter(scene, ctx, transfunc, colors, markersize, strokecolor, strokewidth, marker, marker_offset, rotations, model, positions, size_model, font, markerspace, space)
     broadcast_foreach(positions, colors, markersize, strokecolor,
-        strokewidth, marker, marker_offset, remove_billboard(rotations)) do point, col,
+            strokewidth, marker, marker_offset, remove_billboard(rotations)) do point, col,
             markersize, strokecolor, strokewidth, m, mo, rotation
 
         scale = project_scale(scene, markerspace, markersize, size_model)
@@ -315,6 +317,24 @@ function draw_marker(ctx, marker::Rect, pos, scale, strokecolor, strokewidth, ma
 end
 
 
+function draw_marker(ctx, marker::Matrix{T}, pos, scale,
+        strokecolor #= unused =#, strokewidth #= unused =#,
+        marker_offset, rotation) where T<:Colorant
+
+    # convert marker to Cairo compatible image data
+    argb32_marker = convert.(ARGB32, marker)
+    argb32_marker = permutedims(argb32_marker, (2,1)) # swap x-y for Cairo
+    marker_surf   = Cairo.CairoImageSurface(argb32_marker)
+
+    Cairo.translate(ctx, pos[1]+marker_offset[1], pos[2]+marker_offset[2])
+    Cairo.rotate(ctx, to_2d_rotation(rotation))
+    px_scale = scale ./ size(argb32_marker)
+    Cairo.scale(ctx, px_scale[1], px_scale[2])
+    Cairo.set_source_surface(ctx, marker_surf, 0, 0)
+    Cairo.paint(ctx)
+end
+
+
 ################################################################################
 #                                     Text                                     #
 ################################################################################

CairoMakie/test/runtests.jl

@@ -81,8 +81,6 @@ excludes = Set([
     "Order Independent Transparency",
     "heatmap transparent colormap",
     "fast pixel marker",
-    "Array of Images Scatter",
-    "Image Scatter different sizes",
     "scatter with glow",
     "scatter with stroke",
     "heatmaps & surface"

NEWS.md

@@ -2,6 +2,8 @@
 
 ## master
 
+- Allow `CairoMakie` to render `scatter` with images as markers [#2080](https://github.com/JuliaPlots/Makie.jl/pull/2080).
+
 ## v0.17.13
 
 - Fix boundingboxes [#2184](https://github.com/JuliaPlots/Makie.jl/pull/2184).

ReferenceTests/src/tests/primitives.jl

@@ -146,6 +146,26 @@ end
 end
 
 
+@reference_test "scatter image markers" begin
+    pixel_types = [ RGBA, RGBAf, RGBA{Float16}, ARGB, ARGB{Float16}, RGB, RGBf, RGB{Float16} ]
+    rotations = [ 2pi/3 * (i-1) for i = 1:length(pixel_types) ]
+    s = Scene(resolution = (100+100*length(pixel_types), 400), camera = campixel!)
+    filename = Makie.assetpath("icon_transparent.png")
+    marker_image = FileIO.load(filename)
+    for (i, (rot, pxtype)) in enumerate(zip(rotations, pixel_types))
+        marker = convert.(pxtype, marker_image)
+        p = Point2f((i-1) * 100 + 100, 200)
+        scatter!(s,
+            p,
+            marker = marker,
+            markersize = 75,
+            rotations = rot,
+        )
+    end
+    s
+end
+
+
 @reference_test "basic polygon shapes" begin
     s = Scene(resolution = (800, 800), camera = campixel!)
     scalefactor = 70

WGLMakie/test/runtests.jl

@@ -53,6 +53,7 @@ excludes = Set([
     "Animated surface and wireframe",
     "Array of Images Scatter",
     "Image Scatter different sizes",
+    "scatter image markers",
     "pattern barplot", # not implemented yet
     "scatter with stroke",
     "scatter with glow"