/*
????glfont:??An?example?of?using?the?SDL_ttf?library?with?OpenGL.
????Copyright?（C）?1997-2009?Sam?Lantinga

????This?library?is?free?software;?you?can?redistribute?it?and/or
????modify?it?under?the?terms?of?the?GNU?Library?General?Public
????License?as?published?by?the?Free?Software?Foundation;?either
????version?2?of?the?License?or?（at?your?option）?any?later?version.

????This?library?is?distributed?in?the?hope?that?it?will?be?useful
????but?WITHOUT?ANY?WARRANTY;?without?even?the?implied?warranty?of
????MERCHANTABILITY?or?FITNESS?FOR?A?PARTICULAR?PURPOSE.??See?the?GNU
????Library?General?Public?License?for?more?details.

????You?should?have?received?a?copy?of?the?GNU?Library?General?Public
????License?along?with?this?library;?if?not?write?to?the?Free
????Foundation?Inc.?59?Temple?Place?Suite?330?Boston?MA??02111-1307??USA

????The?SDL_GL_*?functions?in?this?file?are?available?in?the?public?domain.

????Sam?Lantinga
????slouken@libsdl.org
*/

/*?$Id:?glfont.c?4463?2009-03-22?06:54:13Z?slouken?$?*/

/*?A?simple?program?to?test?the?text?rendering?feature?of?the?TTF?library?*/

#include?
#include?
#include?

#include?“SDL.h“
#include?“SDL_ttf.h“

#ifdef?HAVE_OPENGL

#include?“SDL_opengl.h“

#define?DEFAULT_PTSIZE	18
#define?DEFAULT_TEXT	“The?quick?brown?fox?jumped?over?the?lazy?dog“
#define?NUM_COLORS??????256

static?char?*Usage?=
“Usage:?%s?[-utf8|-unicode]?[-b]?[-i]?[-u]?[-fgcol?rgb]?[-bgcol?rgb]?\
.ttf?[ptsize]?[text]\n“;

void?SDL_GL_Enter2DMode（）
{
	SDL_Surface?*screen?=?SDL_GetVideoSurface（）;

	/*?Note?there?may?be?other?things?you?need?to?change
	???depending?on?how?you?have?your?OpenGL?state?set?up.
	*/
	glPushAttrib（GL_ENABLE_BIT）;
	glDisable（GL_DEPTH_TEST）;
	glDisable（GL_CULL_FACE）;
	glEnable（GL_TEXTURE_2D）;

	/*?This?allows?alpha?blending?of?2D?textures?with?the?scene?*/
	glEnable（GL_BLEND）;
	glBlendFunc（GL_SRC_ALPHA?GL_ONE_MINUS_SRC_ALPHA）;

	glViewport（0?0?screen->w?screen->h）;

	glMatrixMode（GL_PROJECTION）;
	glPushMatrix（）;
	glLoadIdentity（）;

	glOrtho（0.0?（GLdouble）screen->w?（GLdouble）screen->h?0.0?0.0?1.0）;

	glMatrixMode（GL_MODELVIEW）;
	glPushMatrix（）;
	glLoadIdentity（）;

	glTexEnvf（GL_TEXTURE_ENV?GL_TEXTURE_ENV_MODE?GL_MODULATE）;
}

void?SDL_GL_Leave2DMode（）
{
	glMatrixMode（GL_MODELVIEW）;
	glPopMatrix（）;

	glMatrixMode（GL_PROJECTION）;
	glPopMatrix（）;

	glPopAttrib（）;
}

/*?Quick?utility?function?for?texture?creation?*/
static?int?power_of_two（int?input）
{
	int?value?=?1;

	while?（?value?		value?<<=?1;
	}
	return?value;
}

GLuint?SDL_GL_LoadTexture（SDL_Surface?*surface?GLfloat?*texcoord）
{
	GLuint?texture;
	int?w?h;
	SDL_Surface?*image;
	SDL_Rect?area;
	Uint32?saved_flags;
	Uint8??saved_alpha;

	/*?Use?the?surface?width?and?height?expanded?to?powers?of?2?*/
	w?=?power_of_two（surface->w）;
	h?=?power_of_two（surface->h）;
	texcoord[0]?=?0.0f;			/*?Min?X?*/
	texcoord[1]?=?0.0f;			/*?Min?Y?*/
	texcoord[2]?=?（GLfloat）surface->w?/?w;	/*?Max?X?*/
	texcoord[3]?=?（GL