Add some utility functions for textures

[libs/gl.git] / source / texture3d.cpp

diff --git a/source/texture3d.cpp b/source/texture3d.cpp
index 5c9f009c0d5eb6d798a06b9a64fd783341430e38..12fc856b8415d4e9cc18ac95c2a9c548a79cf79f 100644 (file)
--- a/source/texture3d.cpp
+++ b/source/texture3d.cpp
@@ -74,8 +74,7 @@ void Texture3D::image(unsigned level, PixelFormat fmt, DataType type, const void
        if(gen_mipmap && level==0)
        {
                auto_generate_mipmap();
-               for(; (w || h || d); w>>=1, h>>=1, d>>=1, ++level) ;
-               allocated |= (1<<level)-1;
+               allocated |= (1<<get_n_levels())-1;
        }
 }
 
@@ -169,7 +168,17 @@ void Texture3D::image(const Graphics::Image &img, bool srgb)
        image(0, fmt, UNSIGNED_BYTE, img.get_data());
 }
 
-void Texture3D::get_level_size(unsigned level, unsigned &w, unsigned &h, unsigned &d)
+unsigned Texture3D::get_n_levels() const
+{
+       unsigned s = max(width, height);
+       if(target!=GL_TEXTURE_2D_ARRAY)
+               s = max(s, depth);
+       unsigned n = 0;
+       for(; s; s>>=1, ++n) ;
+       return n;
+}
+
+void Texture3D::get_level_size(unsigned level, unsigned &w, unsigned &h, unsigned &d) const
 {
        w >>= level;
        h >>= level;