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#ifndef VPYTHON_TEXT_HPP
#define VPYTHON_TEXT_HPP
#pragma once
/* New text rendering organization:
This module defines the platform-independent part of the text renderer.
The public classes are font and layout. layout_texture is only for the use
of the platform-specific font_renderer.
On all platforms, text rendering is expected to work in essentially the same
way: an entire text string is rendered by the platform's text renderer into a
texture (layout), which is then rendered as many times as called for.
Each platform needs to provide {platform}/font_renderer.hpp with the following
public interface (in namespace cvisual):
class font_renderer {
public:
// Create a font_renderer for the requested font.
// Must support 'verdana' or 'sans-serif'
// Should support 'times new roman' or 'serif', and 'courier new' or 'monospace'
font_renderer( const std::wstring& description, int height );
// Returns true if the requested font was available.
bool ok();
// Render text and call tx.set_image()
void gl_render_to_texture( const struct view&, const std::wstring& text, layout_texture& tx );
};
*/
#include "util/texture.hpp"
#include "util/vector.hpp"
namespace cvisual {
class font;
class layout;
class layout_texture : texture {
public: // But only for use by font_renderer!
// Takes similar parameters to glTexImage2D, but always accepts rectangular textures.
// Pass a negative height if the image is bottom-up.
// alignment is GL_UNPACK_ALIGNMENT
// Typically the format should be either GL_ALPHA (for simple antialiasing) or
// GL_RGB or GL_BGR_EXT (for color antialiasing e.g. ClearType)
void set_image( int width, int height, int gl_internal_format, int gl_format, int gl_type, int alignment, void* data );
private:
layout_texture( const boost::shared_ptr<font>& text_font, const std::wstring& text );
~layout_texture();
boost::shared_ptr<font> text_font;
std::wstring text;
virtual void gl_init( const view& );
friend class layout;
vector coord[4];
vector tcoord[4];
int width, height;
int internal_format;
};
class font {
public:
// Call this to get a font. If possible, call only when the font changes.
static boost::shared_ptr<font>
find_font( const std::wstring& desc = std::wstring(), int height = -1);
// Get a layout for some text. This needn't be called with an OpenGL
// context, but it should be called as infrequently as possible (only when
// text changes).
boost::shared_ptr<layout>
lay_out( const std::wstring& text );
private:
friend class layout_texture;
font( class font_renderer* );
boost::weak_ptr<font> self;
boost::scoped_ptr< class font_renderer > renderer;
};
class layout {
public:
// Renders the text with its lower left hand corner (NOT its baseline)
// at the given position.
void gl_render( const view& v, const vector& pos_ll );
// Return the size of the text in pixels (x,y,0)
vector extent( const view& );
private:
friend class font;
layout( const boost::shared_ptr<font>& font, const std::wstring& text );
void draw_quad();
layout_texture tx;
};
} // namespace cvisual
#endif
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