diff options
Diffstat (limited to 'src/mbgl/geometry/dem_data.cpp')
-rw-r--r-- | src/mbgl/geometry/dem_data.cpp | 16 |
1 files changed, 14 insertions, 2 deletions
diff --git a/src/mbgl/geometry/dem_data.cpp b/src/mbgl/geometry/dem_data.cpp index 78134dadc1..7fa98950ea 100644 --- a/src/mbgl/geometry/dem_data.cpp +++ b/src/mbgl/geometry/dem_data.cpp @@ -3,7 +3,7 @@ namespace mbgl { -DEMData::DEMData(const PremultipliedImage& _image): +DEMData::DEMData(const PremultipliedImage& _image, Tileset::DEMEncoding encoding): dim(_image.size.height), border(std::max<int32_t>(std::ceil(_image.size.height / 2), 1)), stride(dim + 2 * border), @@ -13,13 +13,25 @@ DEMData::DEMData(const PremultipliedImage& _image): throw std::runtime_error("raster-dem tiles must be square."); } + auto decodeMapbox = [] (const uint8_t r, const uint8_t g, const uint8_t b){ + // https://www.mapbox.com/help/access-elevation-data/#mapbox-terrain-rgb + return (r * 256 * 256 + g * 256 + b)/10 - 10000; + }; + + auto decodeTerrarium = [] (const uint8_t r, const uint8_t g, const uint8_t b){ + // https://aws.amazon.com/public-datasets/terrain/ + return ((r * 256 + g + b / 256) - 32768); + }; + + auto decodeRGB = encoding == Tileset::DEMEncoding::Terrarium ? decodeTerrarium : decodeMapbox; + std::memset(image.data.get(), 0, image.bytes()); for (int32_t y = 0; y < dim; y++) { for (int32_t x = 0; x < dim; x++) { const int32_t i = y * dim + x; const int32_t j = i * 4; - set(x, y, (_image.data[j] * 256 * 256 + _image.data[j+1] * 256 + _image.data[j+2])/10 - 10000); + set(x, y, decodeRGB(_image.data[j], _image.data[j+1], _image.data[j+2])); } } |