[doc] Add figures/Makefile

doc/figures/FIGURES.t2t

@@ -1,6 +1,10 @@
 List of figures provided with the OwlPS distribution
 
 
+The figures are described below, as well as a way to render the picture
+from the source file. You may also use the ``Makefile`` provided in this
+directory to generate the pictures.
+
 : **Aggregation sequence diagram**
   This is actually a sequence diagram showing the whole process of
   positioning, but it is focused on and best suited to illustrate the
@@ -20,12 +24,16 @@ List of figures provided with the OwlPS distribution
   - Format: [Graphviz http://www.graphviz.org/]
   - PDF conversion command:
 ``` dot -Tpdf -o positioner_input_output.pdf positioner_input_output.dot
+  - PNG conversion: use ``-Tpng`` instead of ``-Tpdf``.
 
 : **OwlPS Positioner's class diagram**
   - File name: ``positioner_class_diagram.uxf``
   - Format: [UMLet http://umlet.com/]
   - PDF conversion command:
-``` umlet -action=convert -format=pdf -filename=positioner_class_diagram.uxf
+``` umlet -action=convert -format=pdf \
+```   -filename=positioner_class_diagram.uxf \
+```   -output=positioner_class_diagram
+  - PNG conversion: use ``-format=png``.
 
 : **OwlPS Positioner's simplified class diagram**
   - File name: ``positioner_class_diagram_simple.plant``
@@ -39,3 +47,4 @@ List of figures provided with the OwlPS distribution
   - Format: [Graphviz http://www.graphviz.org/]
   - PDF conversion command:
 ``` dot -Tpdf -o positioner_process.pdf positioner_process.dot
+  - PNG conversion: use ``-Tpng`` instead of ``-Tpdf``.

doc/figures/Makefile

@@ -0,0 +1,52 @@
+.PHONY: all bitmap pdf clean
+
+all: bitmap
+	@echo
+	@echo "Bitmap files generated successfully."
+	@echo "You can use the 'pdf' target to build PDF files."
+
+bitmap: \
+	owlps_sequence_diagram.png \
+	positioner_input_output.png \
+	positioner_class_diagram.png \
+	positioner_class_diagram_simple.png \
+	positioner_process.png
+
+pdf: \
+	owlps_sequence_diagram.pdf \
+	positioner_input_output.pdf \
+	positioner_class_diagram.pdf \
+	positioner_class_diagram_simple.pdf \
+	positioner_process.pdf
+
+clean:
+	rm -f *.png *.pdf *~
+
+### Generic targets ###
+
+# Graphviz files
+
+%.png: %.dot
+	dot -Tpng -o $@ $<
+
+%.pdf: %.dot
+	dot -Tpdf -o $@ $<
+
+# PlantUML files
+
+%.png: %.plant
+	plantuml -tpng $<
+
+%.eps: %.plant
+	plantuml -teps $<
+
+%.pdf: %.eps
+	epstopdf $<
+
+# UMLet files
+
+%.png: %.uxf
+	umlet -action=convert -format=png -filename=$< -output=$*
+
+%.pdf: %.uxf
+	umlet -action=convert -format=pdf -filename=$< -output=$*