visualize.c

#include "imuread.h"

MagCalibration_t magcal;

Quaternion_t current_orientation;


void apply_calibration(int16_t rawx, int16_t rawy, int16_t rawz, Point_t *out)
{
	float x, y, z;

	x = ((float)rawx * UT_PER_COUNT) - magcal.V[0];
	y = ((float)rawy * UT_PER_COUNT) - magcal.V[1];
	z = ((float)rawz * UT_PER_COUNT) - magcal.V[2];
	out->x = x * magcal.invW[0][0] + y * magcal.invW[0][1] + z * magcal.invW[0][2];
	out->y = x * magcal.invW[1][0] + y * magcal.invW[1][1] + z * magcal.invW[1][2];
	out->z = x * magcal.invW[2][0] + y * magcal.invW[2][1] + z * magcal.invW[2][2];
}

static void quad_to_rotation(const Quaternion_t *quat, float *rmatrix)
{
	float qw = quat->q0;
	float qx = quat->q1;
	float qy = quat->q2;
	float qz = quat->q3;
	rmatrix[0] = 1.0f - 2.0f * qy * qy - 2.0f * qz * qz;
	rmatrix[1] = 2.0f * qx * qy - 2.0f * qz * qw;
	rmatrix[2] = 2.0f * qx * qz + 2.0f * qy * qw;
	rmatrix[3] = 2.0f * qx * qy + 2.0f * qz * qw;
	rmatrix[4] = 1.0f  - 2.0f * qx * qx - 2.0f * qz * qz;
	rmatrix[5] = 2.0f * qy * qz - 2.0f * qx * qw;
	rmatrix[6] = 2.0f * qx * qz - 2.0f * qy * qw;
	rmatrix[7] = 2.0f * qy * qz + 2.0f * qx * qw;
	rmatrix[8] = 1.0f  - 2.0f * qx * qx - 2.0f * qy * qy;
}

static void rotate(const Point_t *in, Point_t *out, const float *rmatrix)
{
	out->x = in->x * rmatrix[0] + in->y * rmatrix[1] + in->z * rmatrix[2];
	out->y = in->x * rmatrix[3] + in->y * rmatrix[4] + in->z * rmatrix[5];
	out->z = in->x * rmatrix[6] + in->y * rmatrix[7] + in->z * rmatrix[8];
}



static GLuint spherelist;
static GLuint spherelowreslist;

int invert_q0=0;
int invert_q1=0;
int invert_q2=0;
int invert_q3=1;
int invert_x=0;
int invert_y=0;
int invert_z=0;

void display_callback(void)
{
	int i;
	float xscale, yscale, zscale;
	float xoff, yoff, zoff;
	float rotation[9];
	Point_t point, draw;
	Quaternion_t orientation;

	quality_reset();
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	glColor3f(1, 0, 0);	// set current color to red
	glLoadIdentity();
#if 0
	gluLookAt(0.0, 0.0, 0.8, // eye location
		  0.0, 0.0, 0.0, // center
		  0.0, 1.0, 0.0); // up direction
#endif
	xscale = 0.05;
	yscale = 0.05;
	zscale = 0.05;
	xoff = 0.0;
	yoff = 0.0;
	zoff = -7.0;

	//if (hard_iron.valid) {
	if (1) {
		memcpy(&orientation, &current_orientation, sizeof(orientation));
		// TODO: this almost but doesn't perfectly seems to get the
		//  real & screen axes in sync....
		if (invert_q0) orientation.q0 *= -1.0f;
		if (invert_q1) orientation.q1 *= -1.0f;
		if (invert_q2) orientation.q2 *= -1.0f;
		if (invert_q3) orientation.q3 *= -1.0f;
		quad_to_rotation(&orientation, rotation);

		//rotation[0] *= -1.0f;
		//rotation[1] *= -1.0f;
		//rotation[2] *= -1.0f;
		//rotation[3] *= -1.0f;
		//rotation[4] *= -1.0f;
		//rotation[5] *= -1.0f;
		//rotation[6] *= -1.0f;
		//rotation[7] *= -1.0f;
		//rotation[8] *= -1.0f;

		for (i=0; i < MAGBUFFSIZE; i++) {
			if (magcal.valid[i]) {
				apply_calibration(magcal.BpFast[0][i], magcal.BpFast[1][i],
					magcal.BpFast[2][i], &point);
				//point.x *= -1.0f;
				//point.y *= -1.0f;
				//point.z *= -1.0f;
				quality_update(&point);
				rotate(&point, &draw, rotation);
				glPushMatrix();
				if (invert_x) draw.x *= -1.0f;
				if (invert_y) draw.y *= -1.0f;
				if (invert_z) draw.z *= -1.0f;
				glTranslatef(
					draw.x * xscale + xoff,
					draw.z * yscale + yoff,
					draw.y * zscale + zoff
				);
				if (draw.y >= 0.0f) {
					glCallList(spherelist);
				} else {
					glCallList(spherelowreslist);
				}
				glPopMatrix();
			}
		}
	}
#if 0
	printf(" quality: %5.1f  %5.1f  %5.1f  %5.1f\n",
		quality_surface_gap_error(),
		quality_magnitude_variance_error(),
		quality_wobble_error(),
		quality_spherical_fit_error());
#endif
}

void resize_callback(int width, int height)
{
	const float ar = (float) width / (float) height;

	glViewport(0, 0, width, height);
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glFrustum(-ar, ar, -1.0, 1.0, 2.0, 100.0);

	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity() ;
}


static const GLfloat light_ambient[]  = { 0.0f, 0.0f, 0.0f, 1.0f };
static const GLfloat light_diffuse[]  = { 1.0f, 1.0f, 1.0f, 1.0f };
static const GLfloat light_specular[] = { 1.0f, 1.0f, 1.0f, 1.0f };
static const GLfloat light_position[] = { 2.0f, 5.0f, 5.0f, 0.0f };

static const GLfloat mat_ambient[]    = { 0.7f, 0.7f, 0.7f, 1.0f };
static const GLfloat mat_diffuse[]    = { 0.8f, 0.8f, 0.8f, 1.0f };
static const GLfloat mat_specular[]   = { 1.0f, 1.0f, 1.0f, 1.0f };
static const GLfloat high_shininess[] = { 100.0f };

void visualize_init(void)
{
	GLUquadric *sphere;

	glClearColor(1.0, 1.0, 1.0, 1.0);
	glEnable(GL_CULL_FACE);
	glCullFace(GL_BACK);
	//glShadeModel(GL_FLAT);
	glEnable(GL_DEPTH_TEST);
	glDepthFunc(GL_LESS);
	glEnable(GL_LIGHT0);
	//glEnable(GL_NORMALIZE);
	glEnable(GL_COLOR_MATERIAL);
	glEnable(GL_LIGHTING);
	glLightfv(GL_LIGHT0, GL_AMBIENT,  light_ambient);
	glLightfv(GL_LIGHT0, GL_DIFFUSE,  light_diffuse);
	glLightfv(GL_LIGHT0, GL_SPECULAR, light_specular);
	glLightfv(GL_LIGHT0, GL_POSITION, light_position);
	glMaterialfv(GL_FRONT, GL_AMBIENT,   mat_ambient);
	glMaterialfv(GL_FRONT, GL_DIFFUSE,   mat_diffuse);
	glMaterialfv(GL_FRONT, GL_SPECULAR,  mat_specular);
	glMaterialfv(GL_FRONT, GL_SHININESS, high_shininess);

	sphere = gluNewQuadric();
	gluQuadricDrawStyle(sphere, GLU_FILL);
	gluQuadricNormals(sphere, GLU_SMOOTH);
	spherelist = glGenLists(1);
	glNewList(spherelist, GL_COMPILE);
	gluSphere(sphere, 0.08, 16, 14);
	glEndList();
	spherelowreslist = glGenLists(1);
	glNewList(spherelowreslist, GL_COMPILE);
	gluSphere(sphere, 0.08, 12, 10);
	glEndList();
	gluDeleteQuadric(sphere);
}