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void setMode(int newmode){    float znear, ymin, ymax, xmin, xmax, aspect, fov;    switch(newmode)    {        case PERSPECTIVE:            glMatrixMode(GL_PROJECTION);            glLoadIdentity();            aspect = VID_WIDTH/VID_HEIGHT;            fov = 90;            ymax = znear * tan(fov * M_PI / 360);            ymin = -ymax;            xmax = ymax * aspect;            xmin = ymin * aspect;            glFrustum(-xmax, xmax, -ymax, ymax, 1.0f, 1024.0f);            glMatrixMode(GL_MODELVIEW);            glLoadIdentity();            this->mode = PERSPECTIVE;        break;        case ORTHO:            glMatrixMode(GL_PROJECTION);            glLoadIdentity();            glOrtho(0.0f, VID_WIDTH, VID_HEIGHT, 0.0f, -1.0f, 1.0f);            glMatrixMode(GL_MODELVIEW);            glDisable(GL_DEPTH_TEST);            glLoadIdentity();            this->mode = ORTHO;        break;    }}initOpenGL(int initialmode){    glViewport(0,0,VID_WIDTH,VID_HEIGHT);    glClearColor(0.4f, 0.4f, 0.4f, 1.0f);    glMatrixMode(GL_PROJECTION);    glLoadIdentity();    glMatrixMode(GL_MODELVIEW);    glLoadIdentity();    glClearDepth(1.0f);    glDepthFunc(GL_EQUAL);    glEnable(GL_DEPTH_TEST);    setMode(initialmode);	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);	glEnable(GL_BLEND);	glEnable(GL_TEXTURE_2D);    glDisable(GL_DITHER);    glShadeModel(GL_SMOOTH);    glDisable(GL_CULL_FACE);    return 0;}