Blocks atlas is auto-assembling now

src/graphics/Atlas.cpp

@@ -0,0 +1,86 @@
+#include "Atlas.h"
+
+#include "../maths/LMPacker.h"
+#include "Texture.h"
+#include "ImageData.h"
+
+using std::vector;
+using std::string;
+using std::unique_ptr;
+using std::shared_ptr;
+using std::unordered_map;
+
+Atlas::Atlas(ImageData* image, 
+             unordered_map<string, UVRegion> regions)
+      : texture(Texture::from(image)),
+        image(image),
+        regions(regions) {        
+}
+
+Atlas::~Atlas() {
+    delete image;
+    delete texture;
+}
+
+bool Atlas::has(string name) const {
+    return regions.find(name) != regions.end();
+}
+
+const UVRegion& Atlas::get(string name) const {
+    return regions.at(name);
+}
+
+Texture* Atlas::getTexture() const {
+    return texture;
+}
+
+ImageData* Atlas::getImage() const {
+    return image;
+}
+
+void AtlasBuilder::add(string name, ImageData* image) {
+    entries.push_back(atlasentry{name, shared_ptr<ImageData>(image)});
+}
+
+Atlas* AtlasBuilder::build(uint extrusion) {
+    unique_ptr<uint[]> sizes (new uint[entries.size() * 2]);
+    for (uint i = 0; i < entries.size(); i++) {
+        auto& entry = entries[i];
+        auto image = entry.image;
+        sizes[i*2] = image->getWidth();
+        sizes[i*2+1] = image->getHeight();
+    }
+    LMPacker packer(sizes.get(), entries.size()*2);
+    sizes.reset(nullptr);
+
+    int width = 32;
+    int height = 32;
+    while (!packer.buildCompact(width, height, extrusion)) {
+        if (width > height) {
+            height *= 2;
+        } else {
+            width *= 2;
+        }
+    }
+
+    unordered_map<string, UVRegion> regions;
+    unique_ptr<ImageData> canvas (new ImageData(ImageFormat::rgba8888, width, height));
+    vector<rectangle> rects = packer.getResult();
+    for (uint i = 0; i < entries.size(); i++) {
+        const rectangle& rect = rects[i];
+        const atlasentry& entry = entries[i];
+        uint x = rect.x;
+        uint y = rect.y;
+        uint w = rect.width;
+        uint h = rect.height;
+        canvas->blit(entry.image.get(), rect.x, rect.y);
+        for (uint j = 0; j < extrusion; j++) {
+            canvas->extrude(x - j, y - j, w + j*2, h + j*2);
+        }
+        float unitX = 1.0f / width;
+        float unitY = 1.0f / height;
+        regions[entry.name] = UVRegion(unitX * x, unitY * y, 
+                                       unitX * (x + w), unitY * (y + h));
+    }
+    return new Atlas(canvas.release(), regions);
+}