1 files changed, 109 insertions, 0 deletions
diff --git a/resource-manager/map_layer.cpp b/resource-manager/map_layer.cpp
new file mode 100644
index 0000000..791972d
--- /dev/null
+++ b/resource-manager/map_layer.cpp
@@ -0,0 +1,109 @@
+
+
+#include "map_layer.h"
+#include "TextureMap.h"
+#include <tmxlite/Layer.hpp>
+#include <tmxlite/TileLayer.hpp>
+
+
+
+MapLayer::MapLayer(){}
+
+MapLayer::~MapLayer(){
+	m_subsets.clear();
+}
+
+bool MapLayer::create(const tmx::Map& map, std::uint32_t layerIndex, const std::vector<TextureMap*>& textures)
+{
+    const auto& layers = map.getLayers();
+    assert(layers[layerIndex]->getType() == tmx::Layer::Type::Tile);
+    
+    const auto& layer = layers[layerIndex]->getLayerAs<tmx::TileLayer>();
+    const auto mapSize = map.getTileCount();
+    const auto mapTileSize = map.getTileSize();
+    const auto& tileSets = map.getTilesets();
+
+    const auto tintColour = layer.getTintColour();
+    const SDL_Colour vertColour =
+    {
+        tintColour.r,
+        tintColour.g,
+        tintColour.b,
+        tintColour.a
+    };
+
+    for (auto i = 0u; i < tileSets.size(); ++i)
+    {
+        //check tile ID to see if it falls within the current tile set
+        const auto& ts = tileSets[i];
+        const auto& tileIDs = layer.getTiles();
+
+        const auto texSize = textures[i]->getSize();
+        const auto tileCountX = texSize.x / mapTileSize.x;
+        const auto tileCountY = texSize.y / mapTileSize.y;
+
+        const float uNorm = static_cast<float>(mapTileSize.x) / texSize.x;
+        const float vNorm = static_cast<float>(mapTileSize.y) / texSize.y;
+
+        std::vector<SDL_Vertex> verts;
+        for (auto y = 0u; y < mapSize.y; ++y)
+        {
+            for (auto x = 0u; x < mapSize.x; ++x)
+            {
+                const auto idx = y * mapSize.x + x;
+                if (idx < tileIDs.size() && tileIDs[idx].ID >= ts.getFirstGID()
+                    && tileIDs[idx].ID < (ts.getFirstGID() + ts.getTileCount()))
+                {
+                    //tex coords
+                    auto idIndex = (tileIDs[idx].ID - ts.getFirstGID());
+                    float u = static_cast<float>(idIndex % tileCountX);
+                    float v = static_cast<float>(idIndex / tileCountY);
+                    u *= mapTileSize.x; //TODO we should be using the tile set size, as this may be different from the map's grid size
+                    v *= mapTileSize.y;
+
+                    //normalise the UV
+                    u /= textures[i]->getSize().x;
+                    v /= textures[i]->getSize().y;
+
+                    //vert pos
+                    const float tilePosX = static_cast<float>(x) * mapTileSize.x;
+                    const float tilePosY = (static_cast<float>(y) * mapTileSize.y);
+
+
+                    //push back to vert array
+                    SDL_Vertex vert = { { tilePosX, tilePosY }, vertColour, {u, v} };
+                    verts.emplace_back(vert);
+                    vert = { { tilePosX + mapTileSize.x, tilePosY }, vertColour, {u + uNorm, v} };
+                    verts.emplace_back(vert);
+                    vert = { { tilePosX, tilePosY + mapTileSize.y}, vertColour, {u, v + vNorm} };
+                    verts.emplace_back(vert);
+                    
+                    vert = { { tilePosX, tilePosY +mapTileSize.y}, vertColour, {u, v + vNorm} };
+                    verts.emplace_back(vert);
+                    vert = { { tilePosX + mapTileSize.x, tilePosY }, vertColour, {u + uNorm, v} };
+                    verts.emplace_back(vert);
+                    vert = { { tilePosX + mapTileSize.x, tilePosY + mapTileSize.y }, vertColour, {u + uNorm, v + vNorm} };
+                    verts.emplace_back(vert);
+                }
+            }
+        }
+
+        if (!verts.empty())
+        {
+            m_subsets.emplace_back();
+            m_subsets.back().texture = *textures[i];
+            m_subsets.back().vertexData.swap(verts);
+        }
+    }
+
+    return true;
+}
+
+void MapLayer::draw(SDL_Renderer* renderer) const
+{
+    assert(renderer);
+    for (const auto& s : m_subsets)
+    {
+        SDL_RenderGeometry(renderer, s.texture, s.vertexData.data(), static_cast<std::int32_t>(s.vertexData.size()), nullptr, 0);
+    }
+}