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Solved
Opengl error
Posted on 2011-03-06
In my opengl project I am creating an animated character in one class and trying to draw i in another class. I am quite new to opengl I have this error that I am struggling with. This one below.
error C2143: syntax error : missing ';' before '->'
It relates to this line of code
Robot->DrawRobot(0.0f, 0.0f, 0.0f);
What does this error mean?
error C2143: syntax error : missing ';' before '->'
It relates to this line of code
Robot->DrawRobot(0.0f, 0.0f, 0.0f);
What does this error mean?
[X]
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5 Comments
>> What does this error mean?
Impossible to say without seeing more of the code.
But there's a good chance that Robot isn't an object.
Btw, this is not an OpenGL error, but a C++ error.
Impossible to say without seeing more of the code.
But there's a good chance that Robot isn't an object.
Btw, this is not an OpenGL error, but a C++ error.
I have posted the class below that creates the robot animated character.
#ifdef _WINDOWS
#include <windows.h>
#endif
//#include <gl/gl.h>
#include <gl/glut.h>
#include "Enemy.h"
Robot::Robot()
{
armAngles[LEFT] = 0.0;
armAngles[RIGHT] = 0.0;
legAngles[LEFT] = 0.0;
legAngles[RIGHT] = 0.0;
armStates[LEFT] = FORWARD_STATE;
armStates[RIGHT] = BACKWARD_STATE;
legStates[LEFT] = FORWARD_STATE;
legStates[RIGHT] = BACKWARD_STATE;
}
Robot::~Robot()
{
}
void Robot::DrawCube(float xPos, float yPos, float zPos)
{
glPushMatrix();
glTranslatef(xPos, yPos, zPos);
glBegin(GL_POLYGON);
glVertex3f(0.0f, 0.0f, 0.0f); // top face
glVertex3f(0.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, 0.0f, 0.0f);
glVertex3f(0.0f, 0.0f, 0.0f); // front face
glVertex3f(-1.0f, 0.0f, 0.0f);
glVertex3f(-1.0f, -1.0f, 0.0f);
glVertex3f(0.0f, -1.0f, 0.0f);
glVertex3f(0.0f, 0.0f, 0.0f); // right face
glVertex3f(0.0f, -1.0f, 0.0f);
glVertex3f(0.0f, -1.0f, -1.0f);
glVertex3f(0.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, 0.0f, 0.0f); // left face
glVertex3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, 0.0f);
glVertex3f(0.0f, 0.0f, 0.0f); // bottom face
glVertex3f(0.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, 0.0f);
glVertex3f(0.0f, 0.0f, 0.0f); // back face
glVertex3f(-1.0f, 0.0f, -1.0f);
glVertex3f(-1.0f, -1.0f, -1.0f);
glVertex3f(0.0f, -1.0f, -1.0f);
glEnd();
glPopMatrix();
}
void Robot::DrawArm(float xPos, float yPos, float zPos)
{
glPushMatrix();
glColor3f(1.0f, 0.0f, 0.0f); // red
glTranslatef(xPos, yPos, zPos);
glScalef(1.0f, 4.0f, 1.0f); // arm is a 1x4x1 cube
DrawCube(0.0f, 0.0f, 0.0f);
glPopMatrix();
}
void Robot::DrawHead(float xPos, float yPos, float zPos)
{
glPushMatrix();
glColor3f(1.0f, 1.0f, 1.0f); // white
glTranslatef(xPos, yPos, zPos);
glScalef(2.0f, 2.0f, 2.0f); // head is a 2x2x2 cube
DrawCube(0.0f, 0.0f, 0.0f);
glPopMatrix();
}
void Robot::DrawTorso(float xPos, float yPos, float zPos)
{
glPushMatrix();
glColor3f(0.0f, 0.0f, 1.0f); // blue
glTranslatef(xPos, yPos, zPos);
glScalef(3.0f, 5.0f, 2.0f); // torso is a 3x5x2 cube
DrawCube(0.0f, 0.0f, 0.0f);
glPopMatrix();
}
void Robot::DrawLeg(float xPos, float yPos, float zPos)
{
glPushMatrix();
glTranslatef(xPos, yPos, zPos);
// draw the foot
glPushMatrix();
glTranslatef(0.0f, -0.5f, 0.0f);
DrawFoot(0.0f, -5.0f, 0.0f);
glPopMatrix();
glScalef(1.0f, 5.0f, 1.0f); // leg is a 1x5x1 cube
glColor3f(1.0f, 1.0f, 0.0f); // yellow
DrawCube(0.0f, 0.0f, 0.0f);
glPopMatrix();
}
void Robot::DrawFoot(float xPos, float yPos, float zPos)
{
glPushMatrix();
glColor3f(1.0f, 1.0f, 1.0f);
glTranslatef(xPos, yPos, zPos);
glScalef(1.0f, 0.5f, 3.0f);
DrawCube(0.0f, 0.0f, 0.0f);
glPopMatrix();
}
void Robot::DrawRobot(float xPos, float yPos, float zPos)
{
glPushMatrix();
glTranslatef(xPos, yPos, zPos); // draw robot at desired coordinates
// draw head and torso parts
DrawHead(1.0f, 2.0f, 0.0f);
DrawTorso(1.5f, 0.0f, 0.0f);
// move the left arm away from the torso and rotate it to give "walking" effect
glPushMatrix();
glTranslatef(0.0f, -0.5f, 0.0f);
glRotatef(armAngles[LEFT], 1.0f, 0.0f, 0.0f);
DrawArm(2.5f, 0.0f, -0.5f);
glPopMatrix();
// move the right arm away from the torso and rotate it to give "walking" effect
glPushMatrix();
glTranslatef(0.0f, -0.5f, 0.0f);
glRotatef(armAngles[RIGHT], 1.0f, 0.0f, 0.0f);
DrawArm(-1.5f, 0.0f, -0.5f);
glPopMatrix();
// move the left leg away from the torso and rotate it to give "walking" effect
glPushMatrix();
glTranslatef(0.0f, -0.5f, 0.0f);
glRotatef(legAngles[LEFT], 1.0f, 0.0f, 0.0f);
DrawLeg(-0.5f, -5.0f, -0.5f);
glPopMatrix();
// move the right leg away from the torso and rotate it to give "walking" effect
glPushMatrix();
glTranslatef(0.0f, -0.5f, 0.0f);
glRotatef(legAngles[RIGHT], 1.0f, 0.0f, 0.0f);
DrawLeg(1.5f, -5.0f, -0.5f);
glPopMatrix();
glPopMatrix(); // pop back to original coordinate system
}
void Robot::Prepare(float dt)
{
// if leg is moving forward, increase angle, else decrease angle
for (char side = 0; side < 2; side++)
{
// arms
if (armStates[side] == FORWARD_STATE)
armAngles[side] += 20.0f * dt;
else
armAngles[side] -= 20.0f * dt;
// change state if exceeding angles
if (armAngles[side] >= 15.0f)
armStates[side] = BACKWARD_STATE;
else if (armAngles[side] <= -15.0f)
armStates[side] = FORWARD_STATE;
// legs
if (legStates[side] == FORWARD_STATE)
legAngles[side] += 20.0f * dt;
else
legAngles[side] -= 20.0f * dt;
// change state if exceeding angles
if (legAngles[side] >= 15.0f)
legStates[side] = BACKWARD_STATE;
else if (legAngles[side] <= -15.0f)
legStates[side] = FORWARD_STATE;
}
}
So, Robot is a type, not an object.
You need to call the DrawRobot method from an instance of the Robot type.
You might want to read up on how to use classes in C++ :
http://www.cplusplus.com/doc/tutorial/classes/
http://www.cplusplus.com/doc/tutorial/classes2/
You need to call the DrawRobot method from an instance of the Robot type.
You might want to read up on how to use classes in C++ :
http://www.cplusplus.com/doc/tutorial/classes/
http://www.cplusplus.com/doc/tutorial/classes2/
This is how I am using my class now.
Robot enemy;
enemy.DrawRobot(1.0f,0.0f,
One more question is there a way I can draw these at random around my world?
Robot enemy;
enemy.DrawRobot(1.0f,0.0f,
One more question is there a way I can draw these at random around my world?
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