#include "glsdlscreen.h"

GLSDLScreen::GLSDLScreen() {
	width = 0;
	height = 1;
	bpp = 16;
	znear = 1.0f;
	zfar = 100.0f;
	
	opengl = false;
	glsetup = true;
	resizable = false;
	fullscreen = false;
	
	extraglparam = 0;
}


int GLSDLScreen::getFlags() {
	const SDL_VideoInfo *videoInfo = SDL_GetVideoInfo();
	int videoflags = 0;
	if(videoInfo->hw_available)
		videoflags |= SDL_HWSURFACE;
	else
		videoflags |= SDL_SWSURFACE;
	if(videoInfo->blit_hw)
		videoflags |= SDL_HWACCEL;
	
	if(opengl) {
		videoflags |= SDL_OPENGL;
		videoflags |= SDL_GL_DOUBLEBUFFER;
		videoflags |= SDL_HWPALETTE;
	}
	
	return videoflags;
}
void GLSDLScreen::enableOpenGL(bool w) {
	opengl = w;
}

void GLSDLScreen::enableResizable(bool w) {
	resizable = w;
}

void GLSDLScreen::enableFullscreen(bool w) {
	fullscreen = w;
}

void GLSDLScreen::setGLNearFar(float _znear, float _zfar) {
	znear = _znear;
	zfar  = _zfar;
}

void GLSDLScreen::enableGLSetup(bool w) {
	glsetup = w;
}

void GLSDLScreen::setExtraGLParamFunc(void (*extrafunc)()) {
	extraglparam = extrafunc;
}

void GLSDLScreen::setVideoMode(int _width, int _height, int _bpp) {
	width = _width;
	height = _height;
	bpp = _bpp;
	
	if(height==0)
		height = 1;
}

bool GLSDLScreen::isOK() {
	return SDL_VideoModeOK(width, height, bpp, getFlags());
}

bool GLSDLScreen::apply() {
	if(!SDL_WasInit(SDL_INIT_VIDEO)) {
		if(SDL_Init(SDL_INIT_VIDEO)==-1) {
			return false;
		}
	}

	screen = SDL_SetVideoMode(width, height, bpp, getFlags());
	
	if(!screen) {
		return false;
	}
	
	if(opengl) {
		SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
			
		
		// Setup GL
		if(glsetup) {
			glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
			glClearDepth(1.0f);
			glDepthFunc(GL_LEQUAL);
			glShadeModel(GL_SMOOTH);
			glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);
			glEnable(GL_ALPHA_TEST);
			glAlphaFunc(GL_GREATER, 0.1);
		}
		
		// Projection
		glViewport(0, 0, (GLsizei)width, (GLsizei)height);
		
		glMatrixMode(GL_PROJECTION);
		glLoadIdentity();
		gluPerspective(45.0f, (GLfloat)width/(GLfloat)height, znear, zfar);
		
		if(extraglparam) {
			extraglparam();
		}
		
		glMatrixMode(GL_MODELVIEW);

		// Texturen neuladen, eigentlich nur für Windows. Aber egal.
		GLTexture::reloadAll();
	}
	
	return true;
}