CMAKE + install command

experimental/c-api-example/c.md

Index: experimental/c-api-example/c.md
diff --git a/experimental/c-api-example/c.md b/experimental/c-api-example/c.md
index 89ad577bb439fa67401760a5a80622c0aac8e68c..12ffe096f784f96248efd588ebcba8fc58cc4441 100644
--- a/experimental/c-api-example/c.md
+++ b/experimental/c-api-example/c.md
@@ -108,36 +108,24 @@ Cmake example
 
 The following proof-of-concept workflow currently works on MacOS and Ubuntu
 
-1.  Aquire Skia (you may have already done this):
+1.  Aquire, compile, and install Skia as a shared library:
 
     <!--?prettify lang=sh?-->
 
-        cd [Wherever you want skia src code]
-        git clone 'https://skia.googlesource.com/skia'
-        SKIA_DIR="$PWD/skia"
+        prefix="$HOME" # or /usr/local or wherever

[mtklein, 2015/09/03 16:32:06]

This seems too complicated to be a clear example.  How about:

  git clone https://skia.googlesource.com/skia
  cd skia/cmake
  cmake .  # Or use your favorite non-default generator, e.g. cmake . -G Ninja
  cmake --build .
  sudo cmake --build . -- install

Let's trust people who want to do fancy things know how to do fancy things.

[hal.canary, 2015/09/03 21:05:24]

I like not depending on ninja.

I want to demonstrate the use of CMAKE_INSTALL_PREFIX, since the syntax is
non-obvious (I once spent days trying to get it right).  Also, I recommend
against installing it in /usr/local right now.

+        cd $(mktemp -d "${TMPDIR:-/tmp}/skia.XXXXXXXXXX")
+        git clone --depth 1 'https://skia.googlesource.com/skia'
+        cmake -DCMAKE_INSTALL_PREFIX:PATH="$prefix" skia/cmake -G Ninja
+        ninja skia
+        ninja install
 
-2.  Compile Skia (outside of source) as a shared library:
+2.  Compile, link, and run the example program:
 
-    <!--?prettify lang=sh?-->
-
-        cd [Wherever you want skia build files]
-        mkdir build_skia
-        cd build_skia
-        SKIA_BUILD="$PWD"
-        cmake "$SKIA_DIR/cmake" -G Ninja && ninja
-
-3.  Compile, link, and run the example program:
-
-    <!--?prettify lang=sh?-->
+    <!--?prettify lang=sh?-->hal2

[mtklein, 2015/09/03 16:32:06]

hal2?

[hal.canary, 2015/09/03 21:05:23]

argh!  that's the name of an emacs macro I have!

 
-        cd [Wherever you want the example]
-        mkdir skia_c_example
-        cd skia_c_example
-        cp "$SKIA_DIR/experimental/c-api-example/skia-c-example.c" .
-        cc -c -I "$SKIA_DIR/include/c" skia-c-example.c -o skia-c-example.o
-        c++ skia-c-example.o \
-            "$SKIA_BUILD"/libskia.* -Wl,-rpath -Wl,"$SKIA_BUILD" \
-            -o skia-c-example
+        cc -o skia-c-example -I "$prefix/include" \

[mtklein, 2015/09/03 16:32:06]

Similarly,

cc -o skia-c-example ../experimental/c-api-example/skia-c-example.c
-I/usr/local/include -L/usr/local/lib -lskia

+            skia/experimental/c-api-example/skia-c-example.c \
+            "$prefix"/lib/libskia.* -Wl,-rpath -Wl,"$prefix/lib"
         ./skia-c-example
-        [ $(uname) = Darwin ] && open skia-c-example.png
-        [ $(uname) = Linux ] && xdg-open skia-c-example.png
+        [ $(uname) = Darwin ] && open     skia-c-example.png
+        [ $(uname) = Linux  ] && xdg-open skia-c-example.png