Add build script to make an (svg) demo of all available themes

.gitignore

@@ -6,6 +6,17 @@ e2e_report.html
 bin
 out
 d2
+# generated svg examples (from make themesdemo)
+testdata/examples/svg/
 
 # https://github.com/golang/go/blob/8b67cf0bc6ad657fddcbaaa10729d0086f08f9a9/src/cmd/go/internal/test/test.go#L415-L416
-e2etests.test
+e2etests.test
+
+# nix/devenv related
+# .envrc
+devenv.*
+!devenv.nix
+.devenv*
+.direnv
+.pre-commit-config.yaml
+

Makefile

@@ -24,3 +24,20 @@ race: fmt
 .PHONY: js
 js: gen
 	cd d2js/js && NPM_VERSION="${NPM_VERSION}" prefix "$@" ./make.sh all
+
+SVGDIR := testdata/examples/svg
+SVGS = $(shell ./d2 themes | gawk -F':' '/^-/{ printf "$(SVGDIR)/themex-%03d.svg ",$$2 }' || :)
+
+.PHONY: clean
+clean:
+	rm -f $(SVGS) d2
+	rmdir $(SVGDIR)
+
+.PHONY: themesdemo
+themesdemo: $(SVGS) d2
+
+$(SVGDIR)/themex-%.svg: testdata/examples/themex.d2 
+	$(info Building $@ from $< ...)
+	./d2 -t $$(( 10#$* )) $< $@
+
+d2: build

testdata/examples/themex.d2

@@ -0,0 +1,50 @@
+
+vars: {
+  d2-config: {
+    layout-engine: elk
+  }
+}
+network: {
+  cell tower: {
+    satellites: {
+      shape: stored_data
+      style.multiple: true
+    }
+
+    transmitter
+
+    satellites -> transmitter: send
+    satellites -> transmitter: send
+    satellites -> transmitter: send
+  }
+
+  online portal: {
+    ui: {shape: hexagon}
+  }
+
+  data processor: {
+    storage: {
+      shape: cylinder
+      style.multiple: true
+    }
+  }
+
+  cell tower.transmitter -> data processor.storage: phone logs
+}
+
+user: {
+  shape: person
+  width: 130
+}
+
+user -> network.cell tower: make call
+user -> network.online portal.ui: access {
+  style.stroke-dash: 3
+}
+
+api server -> network.online portal.ui: display
+api server -> logs: persist
+logs: {shape: page; style.multiple: true}
+
+network.data processor -> api server
+