Fix RenderTexture texture size + add text/font debug output

- Add Texture::setSize() method for RenderTexture to set its texture dimensions
- RenderTexture::create() now sets texture size (was 0,0 causing Sprite::draw to bail)
- Add debug output to FontAtlas::load showing glyph count and non-zero pixels
- Add debug output to Text::draw showing atlas texture ID and colors

These fixes should enable grid rendering (RenderTexture now has proper size).
Debug output will help diagnose why text shows as solid boxes instead of glyphs.

Co-Authored-By: Claude <noreply@anthropic.com>

src/platform/SDL2Renderer.cpp

@@ -1021,6 +1021,7 @@ bool RenderTexture::create(unsigned int width, unsigned int height) {
 
     // Set up internal texture to point to FBO color attachment
     texture_.setNativeHandle(colorTexture);
+    texture_.setSize(width, height);  // Critical: Sprite::draw needs texture size for UV calc
 
     view_ = View(FloatRect(0, 0, static_cast<float>(width), static_cast<float>(height)));
     defaultView_ = view_;
@@ -1575,6 +1576,8 @@ void Sprite::draw(RenderTarget& target, RenderStates states) const {
 // Static cache for font atlases - keyed by (font data pointer, character size)
 static std::map<std::pair<const Font*, unsigned int>, FontAtlas> s_fontAtlasCache;
 
+static int textDebugCount = 0;
+
 void Text::draw(RenderTarget& target, RenderStates states) const {
     if (!font_ || string_.empty() || !font_->isLoaded()) return;
 
@@ -1584,12 +1587,21 @@ void Text::draw(RenderTarget& target, RenderStates states) const {
     if (it == s_fontAtlasCache.end()) {
         FontAtlas atlas;
         if (!atlas.load(font_->getData(), font_->getDataSize(), static_cast<float>(characterSize_))) {
+            std::cerr << "Text::draw: Failed to create font atlas!" << std::endl;
             return;  // Failed to create atlas
         }
+        std::cout << "Text::draw: Created font atlas, textureId=" << atlas.getTextureId() << std::endl;
         it = s_fontAtlasCache.emplace(key, std::move(atlas)).first;
     }
     const FontAtlas& atlas = it->second;
 
+    // Debug: log first few text draws
+    if (textDebugCount < 3) {
+        std::cout << "Text::draw: string='" << string_.substr(0, 20) << "' atlasTexId=" << atlas.getTextureId()
+                  << " fillColor=(" << (int)fillColor_.r << "," << (int)fillColor_.g << "," << (int)fillColor_.b << ")" << std::endl;
+        textDebugCount++;
+    }
+
     Transform combined = states.transform * getTransform();
 
     // Build vertex data for all glyphs
@@ -1904,6 +1916,15 @@ bool FontAtlas::load(const unsigned char* fontData, size_t dataSize, float fontS
 
     textureId_ = SDL2Renderer::getInstance().createTexture(atlasSize, atlasSize, rgbaPixels.data());
 
+    // Debug: Check if any glyph pixels were actually rendered
+    int nonZeroPixels = 0;
+    for (int i = 0; i < atlasSize * atlasSize; ++i) {
+        if (atlasPixels[i] > 0) nonZeroPixels++;
+    }
+    std::cout << "FontAtlas: created " << atlasSize << "x" << atlasSize
+              << " atlas with " << glyphCache_.size() << " glyphs, "
+              << nonZeroPixels << " non-zero pixels, textureId=" << textureId_ << std::endl;
+
     return true;
 }
 

src/platform/SDL2Types.h

@@ -670,6 +670,7 @@ public:
     bool loadFromMemory(const void* data, size_t size);  // Implemented in SDL2Renderer.cpp
 
     Vector2u getSize() const { return size_; }
+    void setSize(unsigned int width, unsigned int height) { size_ = Vector2u(width, height); }
     void setSmooth(bool smooth);  // Implemented in SDL2Renderer.cpp
     bool isSmooth() const { return smooth_; }
     void setRepeated(bool repeated);  // Implemented in SDL2Renderer.cpp