CinderProjectApp.cpp

#include "cinder/app/AppNative.h"  // Contains the AppNative class and the events.
#include "cinder/gl/gl.h"          // Contains most OpenGL convenience functions.

#include "cinder/Camera.h"         // For our camera.

using namespace ci;
using namespace ci::app;
using namespace std;

class CinderProjectApp : public AppNative {
public:
	//! Called once at the start of the application.
	void setup() override;
	//! Called once per frame. Perform your animations here. Don't draw anything.
	void update() override;
	//! Called once per frame. Draw your graphics.
	void draw() override;

	//! Called when the window is resized. Also called at the start of the application.
	void resize() override;

private:
	CameraPersp  mCamera;
	Vec3f        mRotation;
	Vec3f        mTranslation;
};

void CinderProjectApp::setup()
{
	// Setup the camera.
	float verticalFieldOfView = 50.0f;
	float aspectRatio = getWindowAspectRatio(); // See also: resize()
	float nearPlane = 0.1f;
	float farPlane = 10.0f;

	mCamera.setPerspective( verticalFieldOfView, aspectRatio, nearPlane, farPlane );

	Vec3f eye = Vec3f( 0.0f, 0.0f, 0.0f );
	Vec3f center = Vec3f( 0.0f, 0.0f, 1.0f );
	Vec3f up = Vec3f( 0.0f, 1.0f, 0.0f );

	mCamera.lookAt( eye, center, up );

	// Initialize rotation and translation.
	mRotation = Vec3f( 10.0f, 20.0f, 30.0f ); // Angles in degrees for each of the axes.
	mTranslation = Vec3f( 0.0f, 0.0f, 1.0f );
}

void CinderProjectApp::update()
{
	// Let's animate the rotation.
	float seconds = float( getElapsedSeconds() );

	mRotation.x = 180.0f * math<float>::sin( seconds * 0.10f );
	mRotation.y = 180.0f * math<float>::sin( seconds * 0.15f );
	mRotation.z = 180.0f * math<float>::sin( seconds * 0.12f );
}

void CinderProjectApp::draw()
{
	// Clear the color and depth buffers.
	gl::clear();

	// Enable the depth buffer.
	gl::enableDepthRead();
	gl::enableDepthWrite();

	// We are going to adjust scale, rotation and translation,
	// which will change our model matrix. We will also change
	// the view and projection matrix when setting the camera.
	// Store the current matrices so we can later restore them.
	gl::pushMatrices();

	gl::setMatrices( mCamera );

	gl::scale( -1.0f, 1.0f, 1.0f );
	gl::translate( mTranslation );
	gl::rotate( mRotation );

	glBegin( GL_LINES );
	glColor3f( 1.f, 0.f, 0.f );
	glVertex3f( 0.f, 0.f, 0.f );
	glVertex3f( 10.f, 0.f, 0.f );

	glColor3f( 0.f, 1.f, 0.f );
	glVertex3f( 0.f, 0.f, 0.f );
	glVertex3f( 0.f, 10.f, 0.f );

	glColor3f( 0.f, 0.f, 1.f );
	glVertex3f( 0.f, 0.f, 0.f );
	glVertex3f( 0.f, 0.f, 10.f );
	glEnd();

	// Restore matrices.
	gl::popMatrices();

	// If we want to restore OpenGL's state to the way it was
	// at the beginning of this function, we'll have to disable
	// the depth buffer, too.
	gl::disableDepthWrite();
	gl::disableDepthRead();
}

void CinderProjectApp::resize()
{
	// Make sure our camera keeps the correct aspect ratio.
	mCamera.setAspectRatio( getWindowAspectRatio() );
}

//! This line will create the entry point for, and start, the application.
CINDER_APP_NATIVE( CinderProjectApp, RendererGl )