Add some utility functions for textures

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

diff --git a/source/texture3d.cpp b/source/texture3d.cpp
index 8b014aee0c262fb811444c1c44a1fba0083df21e..12fc856b8415d4e9cc18ac95c2a9c548a79cf79f 100644 (file)
--- a/source/texture3d.cpp
+++ b/source/texture3d.cpp
@@ -11,6 +11,15 @@ using namespace std;
 namespace Msp {
 namespace GL {
 
+Texture3D::Texture3D(GLenum t):
+       Texture(t),
+       ifmt(RGB),
+       width(0),
+       height(0),
+       depth(0),
+       allocated(0)
+{ }
+
 Texture3D::Texture3D():
        Texture(GL_TEXTURE_3D),
        ifmt(RGB),
@@ -28,12 +37,15 @@ void Texture3D::storage(PixelFormat fmt, unsigned wd, unsigned ht, unsigned dp)
                throw invalid_operation("Texture3D::storage");
        if(wd==0 || ht==0 || dp==0)
                throw invalid_argument("Texture3D::storage");
+
+       if(MSP_sized_internal_formats)
+               fmt = get_sized_pixelformat(fmt);
        require_pixelformat(fmt);
 
+       ifmt = fmt;
        width = wd;
        height = ht;
        depth = dp;
-       ifmt = fmt;
 }
 
 void Texture3D::allocate(unsigned level)
@@ -62,8 +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;
        }
 }
 
@@ -157,11 +168,22 @@ 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;
-       d >>= level;
+       if(target!=GL_TEXTURE_2D_ARRAY)
+               d >>= level;
 
        if(!w && (h || d))
                w = 1;