com presentations: PHPConf.Asia workshop finish: php-ext-asia18.xml slides/internals/Polar_to_cartesian.svg slides/internal s/coordinates.xml slides/internals/debug.xml slides/int ernals/exercise-steps.xml slides/internals/exercise.xml

diff --git a/php-ext-asia18.xml b/php-ext-asia18.xml
index 4aae017..bcb7114 100644
--- a/php-ext-asia18.xml
+++ b/php-ext-asia18.xml
@@ -55,6 +55,11 @@
 
 <slide>slides/internals/debug.xml</slide>
 
+<slide>slides/internals/exercise.xml</slide>
+<slide>slides/internals/coordinates.xml</slide>
+<slide>slides/internals/exercise-steps.xml</slide>
+
+
 <slide>slides/mongodb/questions.xml</slide>
 <slide>slides/mongodb/resources.xml</slide>
 </presentation>
diff --git a/slides/internals/Polar_to_cartesian.svg b/slides/internals/Polar_to_cartesian.svg
new file mode 100644
index 0000000..b814e0d
--- /dev/null
+++ b/slides/internals/Polar_to_cartesian.svg
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diff --git a/slides/internals/coordinates.xml b/slides/internals/coordinates.xml
new file mode 100644
index 0000000..3e4c809
--- /dev/null
+++ b/slides/internals/coordinates.xml
@@ -0,0 +1,10 @@
+<slide>
+<title>Converting Coordinate Systems</title>
+
+<image filename="Polar_to_cartesian.svg"/>
+
+<list>
+	<bullet>Cartesian: *x* and *y*</bullet>
+	<bullet>Polar: r (*radius*) and φ (*degrees*)</bullet>
+</list>
+</slide>
diff --git a/slides/internals/debug.xml b/slides/internals/debug.xml
new file mode 100644
index 0000000..4bd2adb
--- /dev/null
+++ b/slides/internals/debug.xml
@@ -0,0 +1,12 @@
+<slide>
+<title>Debugging Tools</title>
+
+<blurb>%gdb%</blurb>
+<blurb class="small">→ allows the inspection of programs when they're running</blurb>
+<blurb class="small">→ %export USE_ZEND_ALLOC=0%</blurb>
+<break/>
+
+<blurb>%valgrind%</blurb>
+<blurb class="small">→ tells you about memory corruption and allocation issues</blurb>
+<blurb class="small">→ %export ZEND_DONT_UNLOAD_MODULES=1%</blurb>
+</slide>
diff --git a/slides/internals/exercise-steps.xml b/slides/internals/exercise-steps.xml
new file mode 100644
index 0000000..bd0566c
--- /dev/null
+++ b/slides/internals/exercise-steps.xml
@@ -0,0 +1,26 @@
+<slide>
+<title>Exercise Steps</title>
+<subtitle>Polar to Cartesian Coordinates</subtitle>
+
+<blurb>%geospatial.c%</blurb>
+<list>
+	<bullet>Add the function definition to %geospatial_functions%</bullet>
+	<bullet>Add arg-info struct</bullet>
+	<bullet>Add %PHP_FUNCTION% implementation that uses %zend_parse_parameters% and calls %polar_to_cartesian%</bullet>
+</list>
+
+<blurb>%algorithms.h%</blurb>
+<list>
+	<bullet>Add macro for deg2rad and rad2deg:
+<example><![CDATA[#define deg2rad(deg) ((deg) * M_PI / 180.0)
+#define rad2deg(rad) ((rad) * 180.0 / M_PI)]]></example>
+	</bullet>
+</list>
+
+<blurb>%algorithms.c%</blurb>
+<list>
+	<bullet>Implement algorithm</bullet>
+</list>
+
+<blurb>Run tests!: %make test%</blurb>
+</slide>
diff --git a/slides/internals/exercise.xml b/slides/internals/exercise.xml
new file mode 100644
index 0000000..1533c18
--- /dev/null
+++ b/slides/internals/exercise.xml
@@ -0,0 +1,15 @@
+<slide>
+<title>Exercise</title>
+
+<blurb>Adding new functions to the geospatial extension</blurb>
+
+<blurb>Required:</blurb>
+
+<list>
+	<bullet>Linux, or possibly a Mac</bullet>
+	<bullet>Compiler, automake, autoconf, m4 and friends</bullet>
+	<bullet>PHP, with development headers for PHP 7.0+</bullet>
+	<bullet>A git clone of<br/>%https://github.m/derickr/php-ext-tutorial.git%</bullet>
+	<bullet>PDF of slides for reference:<br/>%:-:url:-:%</bullet>
+</list>
+</slide>