X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=blobdiff_plain;f=source%2Fcore%2Ftexture.h;h=96b17b8910752e0f0f46f7466b2acf7d014e2746;hp=0377c022c30137898da1257571eba01c3dbfd543;hb=HEAD;hpb=b7ecc29c204faede028556d1942b2d61d5cda9ee diff --git a/source/core/texture.h b/source/core/texture.h index 0377c022..96b17b89 100644 --- a/source/core/texture.h +++ b/source/core/texture.h @@ -1,26 +1,36 @@ #ifndef MSP_GL_TEXTURE_H_ #define MSP_GL_TEXTURE_H_ +#include #include #include -#include "gl.h" #include "pixelformat.h" #include "resource.h" +#include "texture_backend.h" namespace Msp { namespace GL { /** -Base class for textures. This class only defines operations common for all -texture types and is not instantiable. For specifying images for textures, -see one of the dimensioned texture classes. +Base class for textures. Most operations are defined in subclasses. -A texture can consinst of a stack of images, called a mipmap. The dimensions -of each mipmap level are half that of the previous level. The mipmap stack -can be used for texture minification; see the Sampler class for details. +Memory must be allocated for the texture by calling storage(). Each subclass +provides this function with parameters appropriate to that type of texture. +Contents can then be modified using the image() and sub_image() functions +provided by subclasses. + +Most types of textures can consist of a pyramid of images, called a mipmap. +The dimensions of each mipmap level are half that of the previous level. + +Textures can be used as either a data source or target for draw commands. To +read from a texture in a shader, it must be paired with a Sampler to determine +how the texels are accessed. To draw into a texture, it must be attached to a +Framebuffer. */ -class Texture: public Resource +class Texture: public TextureBackend, public Resource { + friend TextureBackend; + protected: class Loader: public DataFile::CollectionObjectLoader { @@ -28,10 +38,10 @@ protected: unsigned levels; public: - Loader(Texture &); - Loader(Texture &, Collection &); + Loader(Texture &t): Loader(t, 0) { } + Loader(Texture &t, Collection &c): Loader(t, &c) { } private: - void init(); + Loader(Texture &, Collection *); virtual void finish(); @@ -39,70 +49,66 @@ protected: void load_external_image(Graphics::Image &, const std::string &); private: - void external_image(const std::string &); - void external_image_srgb(const std::string &); - void external_image_common(const std::string &); + void external_data(const std::string &); + void external_image(bool, const std::string &); void generate_mipmap(bool); void image_data(const std::string &); void mipmap_levels(unsigned); + void raw_data(const std::string &); }; - enum FormatSwizzle +public: + class GenericLoader: public DataFile::DynamicObjectLoader { - NO_SWIZZLE, - R_TO_LUMINANCE, - RG_TO_LUMINANCE_ALPHA, - RGB_TO_BGR - }; + friend class Texture; - unsigned id; - GLenum target; - PixelFormat format; - PixelFormat storage_fmt; - FormatSwizzle swizzle; - bool use_srgb_format; - bool auto_gen_mipmap; - std::string debug_name; - - static const int swizzle_orders[]; - static Texture *scratch_binding; - - Texture(GLenum, ResourceManager * = 0); - Texture(const Texture &); - Texture &operator=(const Texture &); -public: - ~Texture(); + public: + GenericLoader(Collection &c): DynamicObjectLoader(&c) { } + + protected: + virtual const TypeRegistry &get_type_registry() const { return get_texture_registry(); } + }; protected: - void generate_id(); + PixelFormat format = NO_PIXELFORMAT; + PixelFormat storage_fmt = NO_PIXELFORMAT; + ComponentSwizzle swizzle = NO_SWIZZLE; + unsigned n_levels = 0; + bool use_srgb_format = false; + bool auto_gen_mipmap = false; + + Texture(unsigned); + void set_format(PixelFormat); - void apply_swizzle(); - void set_parameter_i(GLenum, int) const; + static unsigned count_levels(unsigned); + + void stage_pixels(void *, const void *, std::size_t); public: PixelFormat get_format() const { return format; } - void generate_mipmap(); + using TextureBackend::generate_mipmap; - /// Loads a Graphics::Image from a file and uploads it to the texture. + /** Replaces contents of an entire mipmap level. Allocated storage must + exist. The image data is interpreted according to the storage format and + must have size matching the selected mipmap level. */ + virtual void image(unsigned level, const void *) = 0; + + /** Loads an image into the texture from a file. */ virtual void load_image(const std::string &, unsigned = 0); - /** Uploads an image to the texture. If storage has not been defined, it - will be set to match the image. Otherwise the image must be compatible - with the defined storage. Semantics depend on the type of texture. */ + /** Sets the texture's contents from an image. If storage has not been + allocated yet, it will be set to match the image. Otherwise the image must + be compatible with the existing storage. Subclasses may impose restrictions + on the image's dimensions. */ virtual void image(const Graphics::Image &, unsigned = 0) = 0; - GLenum get_target() const { return target; } - unsigned get_id() const { return id; } - - virtual std::uint64_t get_data_size() const { return 0; } + virtual std::size_t get_data_size() const { return 0; } - void set_debug_name(const std::string &); + using TextureBackend::set_debug_name; -protected: - void bind_scratch(); -public: - static void unbind_scratch(); +private: + static GenericLoader::TypeRegistry &get_texture_registry(); }; } // namespace GL