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#include <common.h>
#include <ctime>
SDL_Window *window = NULL;
SDL_Surface *renderSurface = NULL;
SDL_GLContext mainGLContext = NULL;
bool gameRunning = true;
const float ticksPerSec = 20;
const float msecPerTick = 1000 / ticksPerSec;
int prevTime = GetTickCount();
int currentTime = 0;
float deltaTime = 0;
Entities *entit1;
Player player;
UIClass ui;
World *currentWorld;
float interpolate(float goal, float current, float dt){
float difference = goal - current;
if(difference > dt){
return current + dt;}
if(difference < dt){
return current - dt;}
return goal;
}
void render();
int main(int argc,char **argv){
//runs start-up procedures
if(!SDL_Init(SDL_INIT_VIDEO)){
atexit(SDL_Quit);
if(!(IMG_Init(IMG_INIT_PNG|IMG_INIT_JPG)&(IMG_INIT_PNG|IMG_INIT_JPG))){
std::cout<<"Could not init image libraries!\n"<<std::endl;
return -1;
}
atexit(IMG_Quit);
//Turn on double Buffering
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
//create the window
window = SDL_CreateWindow("Independent Study v.0.1 alpha", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, SCREEN_WIDTH, SCREEN_HEIGHT, SDL_WINDOW_SHOWN | SDL_WINDOW_OPENGL
#ifdef FULLSCREEN
| SDL_WINDOW_FULLSCREEN
#endif // FULLSCREEN
);
if(window){
//set OpenGL context
mainGLContext = SDL_GL_CreateContext(window);
if(mainGLContext == NULL){
std::cout << "The OpenGL context failed to initialize! Error: " << SDL_GetError() << std::endl;
}
}else{
std::cout << "The window failed to generate! Error: " << SDL_GetError() << std::endl;
return -1;
}
}else{
std::cout << "SDL was not able to initialize! Error: " << SDL_GetError() << std::endl;
return -1;
}
srand(time(NULL));
glClearColor(.3,.5,.8,0);
glEnable(GL_BLEND);
glBlendFunc(GL_SRC_ALPHA,GL_ONE_MINUS_SRC_ALPHA);
/**************************
**** GAMELOOP ****
**************************/
entit1 = &player;
entit1->spawn(4, 0);
World *w=NULL;
World *w2=new World(4,w,NULL);
w=new World(2,NULL,w2);
currentWorld=w;
while(gameRunning){
prevTime = currentTime;
currentTime = GetTickCount();
deltaTime = currentTime - prevTime;
if(prevTime + msecPerTick <= GetTickCount()){ //HANDLE ALL LOGIC STUFF HERE
ui.handleEvents(); // Handle events
player.vel.x = 0;
std::cout << player.vel.x << std::endl;
std::cout << player.velg.y << std::endl;
std::cout << "d:" << deltaTime << std::endl;
prevTime = GetTickCount();
}
//DO ALL RENDERING HERE
player.vel.x = interpolate(player.velg.x, player.vel.x, deltaTime) * .001;
if(player.vel.x > .05) player.vel.x = .05;
if(player.vel.x < -.05) player.vel.x = -.05;
player.loci.x += player.vel.x;
render();
}
/**************************
**** CLOSE PROGRAM ****
**************************/
//closes the window and frees resources
SDL_GL_DeleteContext(mainGLContext);
SDL_DestroyWindow(window);
return 0;
}
void render(){
//a matrix is a blank canvas for the computer to draw on, the matrices are stored in a "stack"
//GL_PROJECTION has 2 matrices
//GL_MODELVIEW has 32 matrices
glMatrixMode(GL_PROJECTION); //set the matrix mode as projection so we can set the ortho size and the camera settings later on
glPushMatrix(); //push the matrix to the top of the matrix stack
glLoadIdentity(); //replace the entire matrix stack with the updated GL_PROJECTION mode
glOrtho(-1 + player.loci.x, 1 + player.loci.x , -1, 1, -1,1); //set the the size of the screen
glMatrixMode(GL_MODELVIEW); //set the matrix to modelview so we can draw objects
glPushMatrix(); //push the matrix to the top of the matrix stack
glLoadIdentity(); //replace the entire matrix stack with the updated GL_MODELVIEW mode
glPushMatrix(); //basically here we put a blank canvas (new matrix) on the screen to draw on
glClear(GL_COLOR_BUFFER_BIT); //clear the matrix on the top of the stack
/**************************
**** RENDER STUFF HERE ****
**************************/
currentWorld->draw();
glColor3ub(0,0,0);
glRectf(player.loci.x, player.loci.y, player.loci.x + player.width, player.loci.y + player.height);
/**************************
**** CLOSE THE LOOP ****
**************************/
glPopMatrix(); //take the matrix(s) off the stack to pass them to the renderer
SDL_GL_SwapWindow(window); //give the stack to SDL to render it
}
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