public void setViewport(int x, int y, int w, int h) {
		this.x = x; this.y = y; this.w = w; this.h = h;
		
		if(mainCamera != this) return;
		// ̃JۂɎgpȂAȉ̍Đݒ肪s
		glViewport(x, y, w, h);
		
		glMatrixMode(GL_PROJECTION);
		glLoadIdentity();
		gluPerspective(fovy, (float)w/h, near, far);
		
		glMatrixMode(GL_MODELVIEW);
		glLoadIdentity();
		gluLookAt(eyex, eyey, eyez, centerx, centery, centerz, upx, upy, upz);
	}