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我的OpenGL應用程序出現問題，您可以在this gif中清楚地看到問題。基本上我想按照光標指向的方向移動，但這不會發生，而是「前進」方向保持不變。如何在OpenGL中更新「前進」運動
例如，如果我轉動180°並按下「w」向前走，反而向後走。我正在談論走路，因爲我試圖複製第一人稱相機，就像在FPS遊戲中一樣。
下在這裏你可以看到我到目前爲止已經編寫的代碼：
#include <GL\glew.h>
#include <GL\freeglut.h>
#include <iostream>
#include <cstdlib>
#include "imageLoader.h"
using namespace std;
float _angleY = 0.0f;
float _angleX = 0.0f;
bool about_y = true;
float oldMouseX;
float oldMouseY;
int valid = 0;
float posX = 0.0;
float posZ = 0.0;
// actual vector representing the camera's direction
float lx = 0.0f, lz = -1.0f;
// XZ position of the camera
float x = 0.0f, z = 5.0f;
// the key states. These variables will be zero
// when no key is being presses
float deltaAngle = 0.0f;
float deltaMove = 0;
int xOrigin = -1;
// angle of rotation for the camera direction
float angle = 0.0f;
void mouseMove(int x, int y) {
// this will only be true when the left button is down
if (xOrigin >= 0) {
// update deltaAngle
deltaAngle = (x - xOrigin) * 0.001f;
// update camera's direction
lx = sin(angle + deltaAngle)*2;
lz = -cos(angle + deltaAngle)*2;
}
}
void mouseButton(int button, int state, int x, int y) {
// only start motion if the left button is pressed
if (button == GLUT_LEFT_BUTTON) {
// when the button is released
if (state == GLUT_UP) {
angle += deltaAngle;
xOrigin = -1;
}
else {// state = GLUT_DOWN
xOrigin = x;
}
}
}
void handleKeys(unsigned char key, int x, int y){
switch (key)
{
case 'w':
posZ+=4;
cout << "FORWARD\n";
break;
case 's':
posZ-=4;
cout << "BACK\n";
break;
case 'd':
posX-=4;
cout << "RIGHT\n";
break;
case 'a':
posX+=4;
cout << "LEFT\n";
break;
case 27:
exit(0);
break;
}
}
//initializes 3d rendering
void initRendering(){
glEnable(GL_DEPTH_TEST); //permits one object to show up behind another one
glEnable(GL_COLOR_MATERIAL);
glEnable(GL_LIGHTING); //enables the lighting function
glEnable(GL_LIGHT0); //enables light num. 1
glEnable(GL_LIGHT1); //enables light num. 2
glEnable(GL_NORMALIZE);
Image* image = loadBMP("bricks.bmp");
_textureId = loadTexture(image);
delete image;
}
//handles the resize of the window
void handleResize(int w, int h){
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0, double(w)/double(h), 1.0, 800.0);
}
void computePos(float deltaMove) {
x += deltaMove * lx * 0.1f;
z += deltaMove * lz * 0.1f;
}
//draws the 3D sccene
void drawScene(){
cout << "ANGLE: "<<angle<<"\n";
if (deltaMove){
computePos(deltaMove);
}
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
// Set the camera
gluLookAt(x, 1.0f, z,
x + lx, 1.0f, z + lz,
0.0f, 1.0f, 0.0f);
glTranslatef(posX, 0.0f, posZ);
//HERE WE ADD THE AMBIENT LIGHT
GLfloat ambientColor[] = { 0.3f, 0.3f, 0.3f, 1.0f }; //the first 3 floats represent the //RGB intensity of the light
glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambientColor);
//HERE WE ADD THE POSITIONED LIGHT (WHITE INTENSE)
GLfloat lightColor0[] = { 0.5f, 0.5f, 0.5f, 1.0f }; //LIGHT0 color
GLfloat lightPos0[] = { 4.0f, 0.0f, 8.0f, 1.0f }; //LIGHT0 position is (4,0,8)
glLightfv(GL_LIGHT0, GL_DIFFUSE, lightColor0); //sets color/intensity of the light
glLightfv(GL_LIGHT0, GL_DIFFUSE, lightPos0); //sets position of the light
//HERE WE ADD THE DIRECTIONAL LIGHT (RED)
GLfloat lightColor1[] = { 0.5f, 0.2f, 0.2f, 1.0f }; //LIGHT1 color
GLfloat lightPos1[] = { -1.0f, 0.5f, 0.5f, 0.0f }; //LIGHT1 is coming from (-1,0.5,0.5)
//NOTE: we just have to put the 4th
//parameter to 0.0f to make it directional
glLightfv(GL_LIGHT1, GL_DIFFUSE, lightColor1); //sets color/intensity of the light
glLightfv(GL_LIGHT1, GL_DIFFUSE, lightPos1); //sets position of the light
glColor3f(1.0f, 1.0f, 0.0f); //we set the cube color
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, _textureId);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
//HERE WE DEFINE COORDINATES FOR THE CUBE
glBegin(GL_QUADS);
//Front
glNormal3f(0.0f, 0.0f, 1.0f);
glTexCoord2f(0.0f, 0.0f);
glVertex3f(-40.5f, -40.0f, 40.5f);
glTexCoord2f(1.0f, 0.0f);
glVertex3f(40.5f, -40.0f, 40.5f);
glTexCoord2f(1.0f, 1.0f);
glVertex3f(40.5f, 40.0f, 40.5f);
glTexCoord2f(0.0f, 1.0f);
glVertex3f(-40.5f, 40.0f, 40.5f);
//Right
glNormal3f(1.0f, 0.0f, 0.0f);
glTexCoord2f(0.0f, 0.0f);
glVertex3f(40.5f, -40.0f, -80.5f);
glTexCoord2f(0.0f, 1.0f);
glVertex3f(40.5f, 40.0f, -80.5f);
glTexCoord2f(1.0f, 1.0f);
glVertex3f(40.5f, 40.0f, 40.5f);
glTexCoord2f(1.0f, 0.0f);
glVertex3f(40.5f, -40.0f, 40.5f);
//Back
glNormal3f(0.0f, 0.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f);
glVertex3f(-40.5f, -40.0f, -80.5f);
glTexCoord2f(0.0f, 0.0f);
glVertex3f(-40.5f, 40.0f, -80.5f);
glTexCoord2f(1.0f, 0.0f);
glVertex3f(40.5f, 40.0f, -80.5f);
glTexCoord2f(1.0f, 1.0f);
glVertex3f(40.5f, -40.0f, -80.5f);
//Left
glNormal3f(-1.0f, 0.0f, 0.0f);
glTexCoord2f(0.0f, 0.0f);
glVertex3f(-40.5f, -40.0f, -80.5f);
glTexCoord2f(1.0f, 0.0f);
glVertex3f(-40.5f, -40.0f, 40.5f);
glTexCoord2f(1.0f, 1.0f);
glVertex3f(-40.5f, 40.0f, 40.5f);
glTexCoord2f(0.0f, 1.0f);
glVertex3f(-40.5f, 40.0f, -80.5f);
glEnd();
glutSwapBuffers();
}
//main loop of the program
void update(int value){
glutPostRedisplay();
glutTimerFunc(25, update, 0);
}
也許你應該以你所尋找的方式走？我的意思是，如果你變成180度，那麼前進就會落後。 – outoftime
對不起，也許我對我的問題不是很清楚。假設你正在看着你，你開始走路，你走這條路，一切都很酷。然後你將身體轉向右邊，然後再次開始行走，但不是右轉，而是身體向前移動的方向移動。這幾乎是發生了什麼。 – Andrew
就像我悲傷，你需要走向你面對的方向。 – outoftime