Help understanding some OpenGL stuff
- by shinjuo
I am working with some code to create a triangle that moves with arrow keys. I want to create a second object that moves independently. This is where I am having trouble, I have created the second actor, but cannot get it to move. There is too much code to post it all so I will just post a little and see if anyone can help at all.
ogl_test.cpp
#include "platform.h"
#include "srt/scheduler.h"
#include "model.h"
#include "controller.h"
#include "model_module.h"
#include "graphics_module.h"
class blob : public actor {
public:
blob(float x, float y) : actor(math::vector2f(x, y)) { }
void render() {
transform();
glBegin(GL_TRIANGLES);
glVertex3f(0.25f, 0.0f, -5.0f);
glVertex3f(-.5f, 0.25f, -5.0f);
glVertex3f(-.5f, -0.25f, -5.0f);
glEnd();
end_transform();
}
void update(controller& c, float dt) {
if (c.left_key) {
rho += pi / 9.0f * dt;
c.left_key = false;
}
if (c.right_key) {
rho -= pi / 9.0f * dt;
c.right_key = false;
}
if (c.up_key) {
v += .1f * dt;
c.up_key = false;
}
if (c.down_key) {
v -= .1f * dt;
if (v < 0.0) { v = 0.0; }
c.down_key = false;
}
actor::update(c, dt);
}
};
class enemyOne : public actor {
public:
enemyOne(float x, float y) : actor(math::vector2f(x, y)) { }
void render() {
transform();
glBegin(GL_TRIANGLES);
glVertex3f(0.25f, 0.0f, -5.0f);
glVertex3f(-.5f, 0.25f, -5.0f);
glVertex3f(-.5f, -0.25f, -5.0f);
glEnd();
end_transform();
}
void update(controller& c, float dt) {
if (c.left_key) {
rho += pi / 9.0f * dt;
c.left_key = false;
}
if (c.right_key) {
rho -= pi / 9.0f * dt;
c.right_key = false;
}
if (c.up_key) {
v += .1f * dt;
c.up_key = false;
}
if (c.down_key) {
v -= .1f * dt;
if (v < 0.0) { v = 0.0; }
c.down_key = false;
}
actor::update(c, dt);
}
};
int APIENTRY WinMain(
HINSTANCE hInstance,
HINSTANCE hPrevInstance,
char* lpCmdLine,
int nCmdShow
)
{
model m;
controller control(m);
srt::scheduler scheduler(33);
srt::frame* model_frame = new srt::frame(scheduler.timer(), 0, 1, 2);
srt::frame* render_frame = new srt::frame(scheduler.timer(), 1, 1, 2);
model_frame->add(new model_module(m, control));
render_frame->add(new graphics_module(m));
scheduler.add(model_frame);
scheduler.add(render_frame);
blob* prime = new blob(0.0f, 0.0f);
m.add(prime);
m.set_prime(prime);
enemyOne* primeTwo = new enemyOne(2.0f, 0.0f);
m.add(primeTwo);
m.set_prime(primeTwo);
scheduler.start();
control.start();
return 0;
}
model.h
#include <vector>
#include "vec.h"
const double pi = 3.14159265358979323;
class controller;
using math::vector2f;
class actor {
public:
vector2f P;
float theta;
float v;
float rho;
actor(const vector2f& init_location) :
P(init_location),
rho(0.0),
v(0.0),
theta(0.0)
{ }
virtual void render() = 0;
virtual void update(controller&, float dt) {
float v1 = v;
float theta1 = theta + rho * dt;
vector2f P1 = P + v1 * vector2f(cos(theta1), sin(theta1));
if (P1.x < -4.5f || P1.x > 4.5f) { P1.x = -P1.x; }
if (P1.y < -4.5f || P1.y > 4.5f) { P1.y = -P1.y; }
v = v1;
theta = theta1;
P = P1;
}
protected:
void transform() {
glPushMatrix();
glTranslatef(P.x, P.y, 0.0f);
glRotatef(theta * 180.0f / pi, 0.0f, 0.0f, 1.0f); //Rotate about the z-axis
}
void end_transform() {
glPopMatrix();
}
};
class model {
private:
typedef std::vector<actor*> actor_vector;
actor_vector actors;
public:
actor* _prime;
model() { }
void add(actor* a) {
actors.push_back(a);
}
void set_prime(actor* a) {
_prime = a;
}
void update(controller& control, float dt) {
for (actor_vector::iterator i = actors.begin(); i != actors.end(); ++i) {
(*i)->update(control, dt);
}
}
void render() {
for (actor_vector::iterator i = actors.begin(); i != actors.end(); ++i) {
(*i)->render();
}
}
};
