fix sprites for pixel ratios that are not 1 and 2

- OpenGL ES 2 doesn't allow NPOT textures with wrap-around
- The Sprite object reported the map's pixelRatio, even though it loaded @2x assets
- Copying icons from the sprite into the atlas now uses bilinear scaling to scale up to the actual size

4 files changed, 19 insertions, 0 deletions

diff --git a/test/fixtures/sprites/atlas_reference.bin b/test/fixtures/sprites/atlas_reference.bin
new file mode 100644
index 0000000000..57eb28bd93
--- /dev/null
+++ b/test/fixtures/sprites/atlas_reference.bin
diff --git a/test/fixtures/sprites/atlas_reference.png b/test/fixtures/sprites/atlas_reference.png
new file mode 100644
index 0000000000..86fad30983
--- /dev/null
+++ b/test/fixtures/sprites/atlas_reference.png
diff --git a/test/fixtures/sprites/bright.bin b/test/fixtures/sprites/bright.bin
new file mode 100644
index 0000000000..3aee130074
--- /dev/null
+++ b/test/fixtures/sprites/bright.bin
diff --git a/test/fixtures/sprites/convert_sprite.js b/test/fixtures/sprites/convert_sprite.js
new file mode 100644
index 0000000000..ba4ff5c29f
--- /dev/null
+++ b/test/fixtures/sprites/convert_sprite.js
@@ -0,0 +1,19 @@
+// Converts a PNG image to a custom "image format" that has a uint32_t width/height prefix and then
+// raw RGBA data. We can't use the built-in PNG reading routines because they are reading
+// premultiplied images by default.
+
+var fs = require('fs');
+var zlib = require('zlib');
+var PNG = require('png-js');
+var png = PNG.load('styles/sprites/bright.png');
+png.decodePixels(function(data) {
+    var result = new Buffer(8 + data.length);
+    result.writeUInt32BE(png.width, 0);
+    result.writeUInt32BE(png.height, 4);
+    data.copy(result, 8);
+
+    zlib.deflate(result, function(err, data) {
+        if (err) throw err;
+        fs.writeFileSync('test/fixtures/sprites/bright.bin', data);
+    });
+});