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我已經寫了一些代碼，嘗試在Ubuntu的OpenGL編程，它是一個小會兒，但我曾經有C.有一定的瞭解。由於C++我聽說是首選遊戲編程，我試圖開發語言用它。Linux上的SDL OpenGL新手，這有什麼問題？
這是在與SDL的OpenGL我第一次真正嘗試，到目前爲止，我已經得到了這一點，編譯和運行，但我的相機功能似乎並沒有做任何事情。我知道可能有很多更好的方法來做這種事情，但是我想在開始學習更高級的東西之前先掌握基礎知識。
的main.cpp
#include <iostream>
#include <cmath>
#include "SDL/SDL.h"
#include "SDL/SDL_opengl.h"
int screen_width = 640;
int screen_height = 480;
const int screen_bpp = 32;
float rotqube = 0.9f;
float xpos = 0, ypos = 0, zpos = 0, xrot = 0, yrot = 0, angle=0.0;
float lastx, lasty;
SDL_Surface *screen = NULL; // create a default sdl_surface to render our opengl to
void camera (void) {
glRotatef(xrot,1.0,0.0,0.0); // x-axis (left and right)
glRotatef(yrot,0.0,1.0,0.0); // y-axis (up and down)
glTranslated(-xpos,-ypos,-zpos); // translate the screen to the position
SDL_GL_SwapBuffers();
}
int DrawCube(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glTranslatef(0.0f, 0.0f,-7.0f);
glRotatef(rotqube,0.0f,1.0f,0.0f);
glRotatef(rotqube,1.0f,1.0f,1.0f);
glBegin(GL_QUADS);
glColor3f(0.0f,1.0f,0.0f);
glVertex3f(1.0f, 1.0f,-1.0f);
glVertex3f(-1.0f, 1.0f,-1.0f);
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(1.0f, 1.0f, 1.0f);
glColor3f(1.0f,0.5f,0.0f);
glVertex3f(1.0f,-1.0f, 1.0f);
glVertex3f(-1.0f,-1.0f, 1.0f);
glVertex3f(-1.0f,-1.0f,-1.0f);
glVertex3f(1.0f,-1.0f,-1.0f);
glColor3f(1.0f,0.0f,0.0f);
glVertex3f(1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f,-1.0f, 1.0f);
glVertex3f(1.0f,-1.0f, 1.0f);
glColor3f(1.0f,1.0f,0.0f);
glVertex3f(1.0f,-1.0f,-1.0f);
glVertex3f(-1.0f,-1.0f,-1.0f);
glVertex3f(-1.0f, 1.0f,-1.0f);
glVertex3f(1.0f, 1.0f,-1.0f);
glColor3f(0.0f,0.0f,1.0f);
glVertex3f(-1.0f, 1.0f, 1.0f);
glVertex3f(-1.0f, 1.0f,-1.0f);
glVertex3f(-1.0f,-1.0f,-1.0f);
glVertex3f(-1.0f,-1.0f, 1.0f);
glColor3f(1.0f,0.0f,1.0f);
glVertex3f(1.0f, 1.0f,-1.0f);
glVertex3f(1.0f, 1.0f, 1.0f);
glVertex3f(1.0f,-1.0f, 1.0f);
glVertex3f(1.0f,-1.0f,-1.0f);
glEnd();
SDL_GL_SwapBuffers();
rotqube +=0.9f;
return true;
}
bool init_sdl(void)
{
if(SDL_Init(SDL_INIT_EVERYTHING) != 0)
{
return false;
}
SDL_GL_SetAttribute(SDL_GL_RED_SIZE, 5);
SDL_GL_SetAttribute(SDL_GL_GREEN_SIZE, 5);
SDL_GL_SetAttribute(SDL_GL_BLUE_SIZE, 5);
SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 16);
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
// TODO: Add error check to this screen surface init
screen = SDL_SetVideoMode(screen_width, screen_height, screen_bpp, SDL_OPENGL | SDL_HWSURFACE | SDL_RESIZABLE);
return true;
}
static void init_opengl()
{
float aspect = (float)screen_width/(float)screen_height;
glViewport(0, 0, screen_width, screen_height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(60.0, aspect, 0.1, 100.0);
glMatrixMode(GL_MODELVIEW);
glClearColor(0.0, 0.0 ,0.0, 0);
glEnable(GL_DEPTH_TEST);
}
void heartbeat()
{
float xrotrad, yrotrad;
int diffx, diffy;
SDL_Event event;
while(1)
{
while(SDL_PollEvent(&event))
{
switch(event.type)
{
case SDL_KEYDOWN:
switch(event.key.keysym.sym)
{
case SDLK_ESCAPE:
exit(0);
break;
case SDLK_w:
yrotrad = (yrot/180 * 3.141592654f);
xrotrad = (xrot/180 * 3.141592654f);
xpos += (float)sin(yrotrad);
zpos -= (float)cos(yrotrad);
ypos -= (float)sin(xrotrad);
std::cout << "w pressed" << std::endl;
break;
case SDLK_s:
yrotrad = (yrot/180 * 3.141592654f);
xrotrad = (xrot/180 * 3.141592654f);
xpos -= (float)sin(yrotrad);
zpos += (float)cos(yrotrad);
ypos += (float)sin(xrotrad);
break;
case SDLK_d:
yrotrad = (yrot/180 * 3.141592654f);
xpos += (float)cos(yrotrad) * 0.2;
zpos += (float)sin(yrotrad) * 0.2;
break;
case SDLK_a:
yrotrad = (yrot/180 * 3.141592654f);
xpos -= (float)cos(yrotrad) * 0.2;
zpos -= (float)sin(yrotrad) * 0.2;
break;
default:
break;
}
break;
case SDL_MOUSEMOTION:
diffx=event.motion.x-lastx; //check the difference between the current x and the last x position
diffy=event.motion.y-lasty; //check the difference between the current y and the last y position
lastx=event.motion.x; //set lastx to the current x position
lasty=event.motion.y; //set lasty to the current y position
xrot += (float)diffy; //set the xrot to xrot with the addition of the difference in the y position
yrot += (float)diffx; //set the xrot to yrot with the addition of the difference in the x position
break;
case SDL_QUIT:
exit(0);
break;
case SDL_VIDEORESIZE:
screen = SDL_SetVideoMode(event.resize.w, event.resize.h, screen_bpp, SDL_OPENGL | SDL_HWSURFACE | SDL_RESIZABLE);
screen_width = event.resize.w;
screen_height = event.resize.h;
init_opengl();
std::cout << "Resized to width: " << event.resize.w << " height: " << event.resize.h << std::endl;
break;
default:
break;
}
}
DrawCube();
camera();
SDL_Delay(50);
}
}
int main(int argc, char* argv[])
{
if(init_sdl() != false)
{
std::cout << "SDL Init Successful" << std::endl;
}
init_opengl();
std::cout << "Hello World" << std::endl;
heartbeat(); // this is essentially the main loop
SDL_Quit();
return 0;
}
的Makefile
all:
g++ -o test main.cpp -lSDL -lGL -lGLU
它編譯和運行，我想我只是需要一些幫助，做照相機移動。謝謝