C++ OpenGL Cube not showing up on screen
I have been attempting to use OpenGL with C++ lately and I have come a cross a problem when trying to render a cube with lighting, but it doesn't appear I believe this is due to some kinda of clipping error.
Here is my code. The initialization function:
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glEnable(GL_DEPTH_TEST);
glEnable(GL_COLOR_MATERIAL);
glEnable(GL_LIGHTING); //Enable lighting
glEnable(GL_LIGHT0); //Enable light #0
glEnable(GL_LIGHT1); //Enable light #1
glEnable(GL_NORMALIZE); //Automatically normalize normals
and here is the draw code
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glTranslatef(0.0f, 0.0f, -8.0f);
//Add ambient light
GLfloat ambientColor[] = {0.2f, 0.2f, 0.2f, 1.0f}; //Color (0.2, 0.2, 0.2)
glLightModelfv(GL_LIGHT_MODEL_AMBIENT, ambientColor);
//Add positioned light
GLfloat lightColor0[] = {0.5f, 0.5f, 0.5f, 1.0f}; //Color (0.5, 0.5, 0.5)
GLfloat lightPos0[] = {4.0f, 0.0f, 8.0f, 1.0f}; //Positioned at (4, 0, 8)
glLightfv(GL_LIGHT0, GL_DIFFUSE, lightColor0)开发者_JAVA技巧;
glLightfv(GL_LIGHT0, GL_POSITION, lightPos0);
//Add directed light
GLfloat lightColor1[] = {0.5f, 0.2f, 0.2f, 1.0f}; //Color (0.5, 0.2, 0.2)
//Coming from the direction (-1, 0.5, 0.5)
GLfloat lightPos1[] = {-1.0f, 0.5f, 0.5f, 0.0f};
glLightfv(GL_LIGHT1, GL_DIFFUSE, lightColor1);
glLightfv(GL_LIGHT1, GL_POSITION, lightPos1);
glRotatef(Rotation, 0.0f, 1.0f, 0.0f);
glColor3f(1.0f, 1.0f, 0.0f);
glBegin(GL_QUADS);
//Front
glNormal3f(0.0f, 0.0f, 1.0f);
//glNormal3f(-1.0f, 0.0f, 1.0f);
glVertex3f(-1.5f, -1.0f, 1.5f);
//glNormal3f(1.0f, 0.0f, 1.0f);
glVertex3f(1.5f, -1.0f, 1.5f);
//glNormal3f(1.0f, 0.0f, 1.0f);
glVertex3f(1.5f, 1.0f, 1.5f);
//glNormal3f(-1.0f, 0.0f, 1.0f);
glVertex3f(-1.5f, 1.0f, 1.5f);
//Right
glNormal3f(1.0f, 0.0f, 0.0f);
//glNormal3f(1.0f, 0.0f, -1.0f);
glVertex3f(1.5f, -1.0f, -1.5f);
//glNormal3f(1.0f, 0.0f, -1.0f);
glVertex3f(1.5f, 1.0f, -1.5f);
//glNormal3f(1.0f, 0.0f, 1.0f);
glVertex3f(1.5f, 1.0f, 1.5f);
//glNormal3f(1.0f, 0.0f, 1.0f);
glVertex3f(1.5f, -1.0f, 1.5f);
//Back
glNormal3f(0.0f, 0.0f, -1.0f);
//glNormal3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.5f, -1.0f, -1.5f);
//glNormal3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.5f, 1.0f, -1.5f);
//glNormal3f(1.0f, 0.0f, -1.0f);
glVertex3f(1.5f, 1.0f, -1.5f);
//glNormal3f(1.0f, 0.0f, -1.0f);
glVertex3f(1.5f, -1.0f, -1.5f);
//Left
glNormal3f(-1.0f, 0.0f, 0.0f);
//glNormal3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.5f, -1.0f, -1.5f);
//glNormal3f(-1.0f, 0.0f, 1.0f);
glVertex3f(-1.5f, -1.0f, 1.5f);
//glNormal3f(-1.0f, 0.0f, 1.0f);
glVertex3f(-1.5f, 1.0f, 1.5f);
//glNormal3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.5f, 1.0f, -1.5f);
glEnd();
SwapBuffers(hDC);
Sleep (1);
after following the advice of Keith i attempted to use the gluLookAt like this:
void gluLookAt ( 10.0 , 10.0 , 10.0 , 1.5, -1.0, 1.5, 0.0, 0.0, 1.0 );
but I get an error
|74|error: variable or field `gluLookAt' declared void|
You may need to define the projection matrix.
This can be done with, for example, gluLookAt()
After your edit: gluLookAt
is a function just like glVertex3f
and such. Therefore invoke it by just calling:
gluLookAt(10.0 , 10.0 , 10.0 , 1.5, -1.0, 1.5, 0.0, 0.0, 1.0 );
Note that there is no void
involved in this line of code!
What the compiler sees if there is a void
in front of this line is a variable declaration named gluLookAt
of type void
initialized (constructed) with a bunch of doubles.
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