--- /dev/null
+#ifndef MSP_GL_SAMPLER_H_
+#define MSP_GL_SAMPLER_H_
+
+#include <msp/datafile/objectloader.h>
+#include "gl.h"
+#include "predicate.h"
+
+namespace Msp {
+namespace GL {
+
+enum TextureFilter
+{
+ /// No filtering
+ NEAREST = GL_NEAREST,
+
+ /// Bilinear filtering
+ LINEAR = GL_LINEAR,
+
+ /// Mipmapping without filtering
+ NEAREST_MIPMAP_NEAREST = GL_NEAREST_MIPMAP_NEAREST,
+
+ /// Linear filtering between two mipmap levels
+ NEAREST_MIPMAP_LINEAR = GL_NEAREST_MIPMAP_LINEAR,
+
+ /// Bilinear filtering on the closest mipmap level
+ LINEAR_MIPMAP_NEAREST = GL_LINEAR_MIPMAP_NEAREST,
+
+ /// Trilinear filtering between two mipmap levels
+ LINEAR_MIPMAP_LINEAR = GL_LINEAR_MIPMAP_LINEAR
+};
+
+
+enum TextureWrap
+{
+ /// Tile the texture infinitely
+ REPEAT = GL_REPEAT,
+
+ /// Extend the texels at the edge of the texture to infinity
+ CLAMP_TO_EDGE = GL_CLAMP_TO_EDGE,
+
+ /// Tile the texture, with every other repetition mirrored
+ MIRRORED_REPEAT = GL_MIRRORED_REPEAT
+};
+
+class Texture;
+
+
+/**
+Samplers are used to access texture data in shaders. To use a sampler with a
+texture, bind it to the same texture unit. Each texture has a default sampler
+which is used if no external sampler is bound.
+
+A texture is generally rendered at a size that's either smaller or larger than
+its native size, so that the texture coordinates do not exactly correspond to
+the texels of the texture. The kind of filtering used, if any, is determined
+by the minification and magnification filter parameters. The default is LINEAR
+for magnification and NEAREST_MIPMAP_LINEAR for minification.
+
+If texture coordinates fall outside of the principal range of the texture,
+wrapping is applied. The default for all directions is REPEAT.
+*/
+class Sampler
+{
+public:
+ class Loader: public DataFile::ObjectLoader<Sampler>
+ {
+ public:
+ Loader(Sampler &);
+ private:
+ void init();
+
+ void filter(TextureFilter);
+ void mag_filter(TextureFilter);
+ void max_anisotropy(float);
+ void min_filter(TextureFilter);
+ void wrap(TextureWrap);
+ void wrap_r(TextureWrap);
+ void wrap_s(TextureWrap);
+ void wrap_t(TextureWrap);
+ };
+
+private:
+ enum ParameterMask
+ {
+ MIN_FILTER = 1,
+ MAG_FILTER = 2,
+ MAX_ANISOTROPY = 4,
+ WRAP_S = 8,
+ WRAP_T = 16,
+ WRAP_R = 32,
+ COMPARE = 64
+ };
+
+ unsigned id;
+ const Texture *owner;
+ TextureFilter min_filter;
+ TextureFilter mag_filter;
+ float max_anisotropy;
+ TextureWrap wrap_s;
+ TextureWrap wrap_t;
+ TextureWrap wrap_r;
+ bool compare;
+ Predicate cmp_func;
+ mutable int dirty_params;
+
+public:
+ Sampler();
+ Sampler(const Texture &);
+private:
+ void init();
+
+ void update_parameter(int) const;
+ void set_parameter_i(unsigned, int) const;
+ void set_parameter_f(unsigned, float) const;
+
+public:
+ void set_min_filter(TextureFilter);
+ void set_mag_filter(TextureFilter);
+
+ /** Sets filter for both minification and magnification. If a mipmapping
+ filter is specified, LINEAR is used for magnification. */
+ void set_filter(TextureFilter);
+
+ TextureFilter get_min_filter() const { return min_filter; }
+ TextureFilter get_mag_filter() const { return mag_filter; }
+
+ void set_max_anisotropy(float);
+ float get_max_anisotropy() const { return max_anisotropy; }
+
+ /** Sets the wrapping mode for all coordinates. */
+ void set_wrap(TextureWrap);
+
+ void set_wrap_s(TextureWrap);
+ void set_wrap_t(TextureWrap);
+ void set_wrap_r(TextureWrap);
+
+ /** Disables depth comparison. */
+ void disable_compare();
+
+ /** Enables depth comparison and sets the compare function. Only has an
+ effect when used with a depth texture. When depth comparison is enabled,
+ the third component of the texture coordinate is compared against the texel
+ value, and the result is returned as the texture sample.*/
+ void set_compare(Predicate);
+
+ bool is_compare_enabled() const { return compare; }
+ Predicate get_compare_function() const { return cmp_func; }
+
+ void bind() const { bind_to(0); }
+ void bind_to(unsigned) const;
+
+ void unload();
+};
+
+
+bool is_mipmapped(TextureFilter);
+
+void operator>>(const LexicalConverter &, TextureFilter &);
+void operator>>(const LexicalConverter &, TextureWrap &);
+
+} // namespace GL
+} // namespace Msp
+
+#endif