1 files changed, 54 insertions, 0 deletions
diff --git a/src/mbgl/geometry/dem_pyramid.hpp b/src/mbgl/geometry/dem_pyramid.hpp
new file mode 100644
index 000000000..d115f191c
--- /dev/null
+++ b/src/mbgl/geometry/dem_pyramid.hpp
@@ -0,0 +1,54 @@
+#pragma once
+
+#include <mbgl/math/clamp.hpp>
+#include <mbgl/util/image.hpp>
+
+#include <memory>
+#include <array>
+#include <cassert>
+#include <vector>
+
+namespace mbgl {
+
+class DEMPyramid {
+public:
+    class Level {
+    public:
+        Level(int32_t width, int32_t height, size_t border);
+
+        void set(const int32_t x, const int32_t y, const int32_t value) {
+            reinterpret_cast<int32_t*>(image.data.get())[idx(x, y)] = value + 65536;
+        }
+
+        int32_t get(const int32_t x, const int32_t y) const {
+            return reinterpret_cast<const int32_t*>(image.data.get())[idx(x, y)] - 65536;
+        }
+
+        void resample(Level& target);
+
+    private:
+        size_t idx(const int32_t x, const int32_t y) const {
+            assert(x >= -border);
+            assert(x < width + border);
+            assert(y >= -border);
+            assert(y < height + border);
+            return (y + border) * stride + (x + border);
+        }
+
+    public:
+        const int32_t width;
+        const int32_t height;
+        const int32_t border;
+        const int32_t stride;
+        PremultipliedImage image;
+    };
+
+
+    void buildLevels();
+
+    std::vector<Level> levels;
+
+
+};
+
+} // namespace mbgl