refactor + auto max atlas resolution

src/assets/assetload_funcs.cpp

@@ -102,7 +102,7 @@ assetload::postfunc assetload::atlas(
             continue;
     }
     std::set<std::string> names = builder.getNames();
-    Atlas* atlas = builder.build(2);
+    Atlas* atlas = builder.build(2, false);
     return [=](auto assets) {
         atlas->prepare();
         assets->store(atlas, name);

src/graphics/core/Atlas.cpp

@@ -5,10 +5,17 @@
 #include "Texture.h"
 #include "ImageData.h"
 
-Atlas::Atlas(ImageData* image, std::unordered_map<std::string, UVRegion> regions)
-  : texture(nullptr),
-    image(image),
-    regions(regions) {        
+Atlas::Atlas(
+    std::unique_ptr<ImageData> image, 
+    std::unordered_map<std::string, UVRegion> regions,
+    bool prepare
+) : texture(nullptr),
+    image(std::move(image)),
+    regions(regions) 
+{        
+    if (prepare) {
+        this->prepare();
+    }
 }
 
 Atlas::~Atlas() {
@@ -43,7 +50,10 @@ bool AtlasBuilder::has(const std::string& name) const {
     return names.find(name) != names.end();
 }
 
-Atlas* AtlasBuilder::build(uint extrusion, uint maxResolution) {
+Atlas* AtlasBuilder::build(uint extrusion, bool prepare, uint maxResolution) {
+    if (maxResolution == 0) {
+        maxResolution = Texture::MAX_RESOLUTION;
+    }
     auto sizes = std::make_unique<uint[]>(entries.size() * 2);
     uint index = 0;
     for (auto& entry : entries) {
@@ -63,8 +73,9 @@ Atlas* AtlasBuilder::build(uint extrusion, uint maxResolution) {
             width *= 2;
         }
         if (width > maxResolution || height > maxResolution) {
-            throw std::runtime_error("max atlas resolution "+
-                                     std::to_string(maxResolution)+" exceeded");
+            throw std::runtime_error(
+                "max atlas resolution "+std::to_string(maxResolution)+" exceeded"
+            );
         }
     }
 
@@ -88,5 +99,5 @@ Atlas* AtlasBuilder::build(uint extrusion, uint maxResolution) {
             unitX * x, unitY * y, unitX * (x + w), unitY * (y + h)
         );
     }
-    return new Atlas(canvas.release(), regions);
+    return new Atlas(std::move(canvas), regions, prepare);
 }

src/graphics/core/Atlas.h

@@ -17,7 +17,14 @@ class Atlas {
     std::unique_ptr<ImageData> image;
     std::unordered_map<std::string, UVRegion> regions;
 public:
-    Atlas(ImageData* image, std::unordered_map<std::string, UVRegion> regions);
+    /// @param image atlas raster
+    /// @param regions atlas regions
+    /// @param prepare generate texture (.prepare())
+    Atlas(
+        std::unique_ptr<ImageData> image, 
+        std::unordered_map<std::string, UVRegion> regions, 
+        bool prepare
+    );
     ~Atlas();
 
     void prepare();
@@ -43,7 +50,12 @@ public:
     bool has(const std::string& name) const;
     const std::set<std::string>& getNames() { return names; };
 
-    Atlas* build(uint extrusion, uint maxResolution=8192);
+    /// @brief Build atlas from all added images
+    /// @param extrusion textures extrusion pixels 
+    /// (greather is less mip-mapping artifacts)
+    /// @param prepare generate atlas texture (calls .prepare()) 
+    /// @param maxResolution max atlas resolution
+    Atlas* build(uint extrusion, bool prepare=true, uint maxResolution=0);
 };
 
 #endif // GRAPHICS_CORE_ATLAS_H_

src/graphics/core/Texture.cpp

@@ -6,6 +6,8 @@
 #include "ImageData.h"
 #include "gl_util.h"
 
+uint Texture::MAX_RESOLUTION = 1024; // Window.initialize overrides it
+
 Texture::Texture(uint id, uint width, uint height) 
     : id(id), width(width), height(height) {
 }

src/graphics/core/Texture.h

@@ -11,6 +11,8 @@ protected:
     uint width;
     uint height;
 public:
+    static uint MAX_RESOLUTION;
+
     Texture(uint id, uint width, uint height);
     Texture(ubyte* data, uint width, uint height, ImageFormat format);
     virtual ~Texture();

src/graphics/render/BlocksPreview.cpp

@@ -143,6 +143,5 @@ std::unique_ptr<Atlas> BlocksPreview::build(
 
     Window::viewport(0, 0, Window::width, Window::height);
     auto newAtlas = std::unique_ptr<Atlas>(builder.build(2));
-    newAtlas->prepare();
     return newAtlas;
 }

src/window/Window.cpp

@@ -3,6 +3,7 @@
 #include "Events.h"
 #include "../debug/Logger.h"
 #include "../graphics/core/ImageData.h"
+#include "../graphics/core/Texture.h"
 
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
@@ -145,6 +146,13 @@ int Window::initialize(DisplaySettings& settings){
     glEnable(GL_BLEND);
     glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 
+    GLint maxTextureSize[1]{static_cast<GLint>(Texture::MAX_RESOLUTION)};
+    glGetIntegerv(GL_MAX_TEXTURE_SIZE, maxTextureSize);
+    if (maxTextureSize[0] > 0) {
+        Texture::MAX_RESOLUTION = maxTextureSize[0];
+        logger.info() << "max texture size is " << Texture::MAX_RESOLUTION;
+    }
+
     glfwSetKeyCallback(window, key_callback);
     glfwSetMouseButtonCallback(window, mouse_button_callback);
     glfwSetCursorPosCallback(window, cursor_position_callback);