Update the build system to use a Makefile.

This allows for a 'mixin' approach when building the image and means it doesn't
derive from the `geodata/gdal` image any more but uses `ubuntu:trusty` instead.

docker/Dockerfile

@@ -7,27 +7,13 @@
 # Builder software (https://github.com/geo-data/cesium-terrain-builder).
 #
 
-FROM geodata/gdal:latest
+# Ubuntu 14.04 Trusty Tahyr
+FROM ubuntu:trusty
 MAINTAINER Homme Zwaagstra <[email protected]>
 
-# Install as root
-USER root
-
-# Upgrade from gcc 4.6 to 4.7 (see
-# http://askubuntu.com/questions/113291/how-do-i-install-gcc-4-7)
-RUN add-apt-repository -y ppa:ubuntu-toolchain-r/test
-RUN apt-get update -y
-RUN apt-get install -y gcc-4.7 g++-4.7
-RUN apt-get remove -y gcc-4.6
-RUN update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-4.7 40 --slave /usr/bin/g++ g++ /usr/bin/g++-4.7
-
-# Ensure `cmake` is present
-RUN apt-get install -y cmake
-
-# Install Cesium Terrain Builder itself
-ADD ./ctb-checkout.txt /tmp/ctb-checkout.txt
-ADD ./install-ctb.sh /tmp/
-RUN sh /tmp/install-ctb.sh
-
-# Clean up APT when done
-RUN apt-get clean && rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/*
+# Install the application.
+ADD . /usr/local/src/cesium-terrain-builder/
+RUN apt-get update -y && \
+    apt-get install -y make && \
+    make -C /usr/local/src/cesium-terrain-builder install clean && \
+    apt-get purge -y make

docker/Makefile

@@ -0,0 +1,60 @@
+##
+# Install Cesium Terrain Builder from within a docker container
+#
+# This Makefile is designed to be run from within a docker container in order to
+# install Cesium Terrain Builder.  The following is an example invocation:
+#
+# make -C /usr/local/src/cesium-terrain-builder install clean
+#
+
+# Version related variables.
+CTB_VERSION := $(shell cat ./ctb-checkout.txt)
+GDAL_VERSION := $(shell cat ./gdal-checkout.txt)
+
+# CTB dependency targets.
+CTB := /usr/local/bin/ctb-tile
+GDAL_CONFIG := /usr/local/bin/gdal_config
+CTB_SRC := /tmp/cesium-terrain-builder-$(CTB_VERSION)
+
+# Build tools.
+WGET := /usr/bin/wget
+
+install: $(CTB)
+
+$(CTB): $(CTB_SRC) /tmp/ctb-build $(GDAL_CONFIG)
+	cd /tmp/ctb-build \
+	&& cmake $(CTB_SRC) \
+	&& make -j$$(nproc) \
+	&& make install \
+	&& ldconfig \
+	&& touch -c $(CTB)
+
+/tmp/ctb-build:
+	mkdir -p /tmp/ctb-build
+
+$(CTB_SRC): $(WGET)
+	$(WGET) --no-verbose "https://github.com/geo-data/cesium-terrain-builder/archive/$(CTB_VERSION).tar.gz" -O $(CTB_SRC).tar.gz \
+	&& tar -C /tmp -xzf $(CTB_SRC).tar.gz \
+	&& touch -c $(CTB_SRC)
+
+$(GDAL_CONFIG): /usr/local/src/gdal-docker
+	make -C /usr/local/src/gdal-docker install \
+	&& touch -c $(GDAL_CONFIG)
+/usr/local/src/gdal-docker: $(WGET)
+	$(WGET) --no-verbose "https://github.com/geo-data/gdal-docker/archive/$(CTB_VERSION).tar.gz" -O /tmp/gdal-docker-$(GDAL_VERSION).tar.gz \
+	&& tar -C /tmp -xzf /tmp/gdal-docker-$(GDAL_VERSION).tar.gz \
+	&& mv /tmp/gdal-docker-$(GDAL_VERSION) /usr/local/src/gdal-docker \
+	&& touch -c /usr/local/src/gdal-docker
+
+$(WGET): /tmp/apt-updated
+	apt-get install -y wget && touch -c $(WGET)
+
+/tmp/apt-updated:
+	apt-get update -y && touch /tmp/apt-updated
+
+# Remove build time dependencies. Delegate to gdal-docker clean as this removes
+# everything, including wget.
+clean:
+	make -C /usr/local/src/gdal-docker clean
+
+.PHONY: install clean

docker/gdal-checkout.txt

@@ -0,0 +1 @@
+master