Background.cpp

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#include "Background.h"
#include "Game.h"
#include <iostream>
using namespace std;

Background::Background( std::string name, std::string filename, bool wrap, Point2D pos) :
WorldObject(name, pos, -10000),
        wrapping(wrap)
{
        load(filename);
        cout<<"background \""<<mName<<"\" created"<<endl;       
}

Background::~Background(){
        glDeleteTextures(1,&mBackground.image);
        for(unsigned int i=0,end=collisionData.size(); i<end; ++i)
                delete collisionData[i];
}

void Background::draw() {
        glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
        glColor4f(1, 1, 1, mTransparency);
        glLoadIdentity();
        //cam pos
        Point2D movePos=mPos-Game::game()->mCamera.pos;
        glTranslated(movePos.x, movePos.y, 0);//move to position
        glRotatef(mAngle,0.0f,0.0f,1.0f);//rotate shape
        glScaled(mScale, mScale, mScale);
        glBindTexture(GL_TEXTURE_2D, mBackground.image);
        glBegin( GL_QUADS );
        // Top-left vertex (corner)
        glTexCoord2f( 0, 0 );
        glVertex3d( 0, 0, 0 );

        // Bottom-left vertex (corner)
        glTexCoord2f( 1, 0 );
        glVertex3d( width, 0, 0 );

        // Bottom-right vertex (corner)
        glTexCoord2f( 1, 1 );
        glVertex3d( width, height, 0 );

        // Top-right vertex (corner)
        glTexCoord2f( 0, 1 );
        glVertex3d( 0, height, 0 );
        glEnd();
        glLoadIdentity();
        //revert to default texture
        glBindTexture(GL_TEXTURE_2D, 0);
}

void Background::update() {
        if(mUnused) return;
        WorldObject::update();
}


int Background::load(std::string filename) {
        SDL_Surface *temp=NULL;
        if((temp = LoadImage("Backgrounds/"+filename)) == NULL) return -1;//Load image for Frame
        cout<<"Loaded file"<<endl;

        //SDL_SetColorKey(temp, SDL_SRCCOLORKEY, SDL_MapRGB(temp->format, transparency[0], transparency[1], transparency[2]));

        SDL_Surface* surface = SDL_DisplayFormatAlpha(temp);
        SDL_FreeSurface(temp);
        width=surface->w;
        height=surface->h;

        // Check that the image’s width is a power of 2
        if ( (surface->w & (surface->w - 1)) != 0 ) {
                cout<<"warning: "<<filename<<"'s width is not a power of 2"<<endl;
        }

        // Also check if the height is a power of 2
        if ( (surface->h & (surface->h - 1)) != 0 ) {
                cout<<"warning: "<<filename<<"'s height is not a power of 2"<<endl;
        }

        //get number of channels in the SDL surface
        GLint nofcolors=surface->format->BytesPerPixel;

        GLenum texture_format=0;

        //contains an alpha channel
        if(surface->format->Rmask==0x000000ff)
                texture_format=GL_RGBA;
        else
                texture_format=GL_BGRA;
        if(!(nofcolors==4 || nofcolors==3))
        {
                cout<<"warning: the image is not truecolor...this will break "<<endl;
        }

        // allocate a texture name
        glGenTextures( 1, &mBackground.image );

        // select our current texture
        glBindTexture( GL_TEXTURE_2D, mBackground.image );

        // select modulate to mix texture with color for shading
        glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE );

        // when texture area is small, bilinear filter the closest mipmap
        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        // when texture area is large, bilinear filter the original
        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR );

        // the texture wraps over at the edges (repeat)
        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP );
        glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP );

        glTexImage2D( GL_TEXTURE_2D, 0, nofcolors, surface->w, surface->h, 0,
                texture_format, GL_UNSIGNED_BYTE, surface->pixels );
        
        SDL_FreeSurface(surface);
        return 0;
}

void Background::setWrap(bool tf) {
        wrapping=tf;
}

bool Background::getWrap() {
        return wrapping;
}

void Background::drawCollisions() {
        WorldObject::drawCollisions(collisionData, mPos);
}