[build] rework platform/default directory and add -files.txt for vendored libs

1 files changed, 31 insertions, 0 deletions

diff --git a/platform/default/src/mbgl/util/image.cpp b/platform/default/src/mbgl/util/image.cpp
new file mode 100644
index 0000000000..25063892b7
--- /dev/null
+++ b/platform/default/src/mbgl/util/image.cpp
@@ -0,0 +1,31 @@
+#include <mbgl/util/image.hpp>
+#include <mbgl/util/string.hpp>
+#include <mbgl/util/premultiply.hpp>
+
+namespace mbgl {
+
+PremultipliedImage decodePNG(const uint8_t*, size_t);
+PremultipliedImage decodeJPEG(const uint8_t*, size_t);
+
+PremultipliedImage decodeImage(const std::string& string) {
+    const auto* data = reinterpret_cast<const uint8_t*>(string.data());
+    const size_t size = string.size();
+
+    if (size >= 4) {
+        uint32_t magic = (data[0] << 24) | (data[1] << 16) | (data[2] << 8) | data[3];
+        if (magic == 0x89504E47U) {
+            return decodePNG(data, size);
+        }
+    }
+
+    if (size >= 2) {
+        uint16_t magic = ((data[0] << 8) | data[1]) & 0xffff;
+        if (magic == 0xFFD8) {
+            return decodeJPEG(data, size);
+        }
+    }
+
+    throw std::runtime_error("unsupported image type");
+}
+
+} // namespace mbgl