void get_model_matrix(float result[16])
{
mat4f_identity(result);
if(fitToView == 0)
{
/* Translate the model to where we were asked to put it */
float translate[16];
mat4f_translateVec_new(translate, placeToPutModel);
/* Do inches to meters conversion if we are asked to. */
float scale[16];
mat4f_identity(scale);
if(INCHES_TO_METERS)
{
float inchesToMeters=1/39.3701;
mat4f_scale_new(scale, inchesToMeters, inchesToMeters, inchesToMeters);
}
mat4f_mult_mat4f_new(result, translate, scale);
return;
}
/* Get a matrix to scale+translate the model based on the bounding
* box. If the last parameter is 1, the bounding box will sit on
* the XZ plane. If it is set to 0, the bounding box will be
* centered at the specified point. */
float fitMatrix[16];
kuhl_bbox_fit(fitMatrix, bbox, 1);
/* Get a matrix that moves the model to the correct location. */
float moveToLookPoint[16];
mat4f_translateVec_new(moveToLookPoint, placeToPutModel);
/* Create a single model matrix. */
mat4f_mult_mat4f_new(result, moveToLookPoint, fitMatrix);
}
/** Some VRPN orientation sensors may be rotated differently than what we
* expect them to be (for example, orientation is correct except that
* the camera is pointing in the wrong direction). This function will
* adjust the orientation matrix so that the camera is pointing in the
* correct direction. */
static void viewmat_fix_rotation(float orient[16])
{
// Fix rotation for a hard-wired orientation sensor.
if(viewmat_control_mode == VIEWMAT_CONTROL_ORIENT)
{
float adjustLeft[16] = { 0, 1, 0, 0,
0, 0, 1, 0,
1, 0, 0, 0,
0, 0, 0, 1 };
mat4f_transpose(adjustLeft); // transpose to column-major order
float adjustRight[16] = { 0, 0, -1, 0,
-1, 0, 0, 0,
0, 1, 0, 0,
0, 0, 0, 1 };
mat4f_transpose(adjustRight);
mat4f_mult_mat4f_new(orient, adjustLeft, orient);
mat4f_mult_mat4f_new(orient, orient, adjustRight);
return;
}
// Fix rotation for VRPN
if(viewmat_vrpn_obj == NULL || strlen(viewmat_vrpn_obj) == 0)
return;
char *hostname = vrpn_default_host();
if(hostname == NULL)
return;
/* Some objects in the IVS lab need to be rotated to match the
* orientation that we expect. Apply the fix here. */
if(vrpn_is_vicon(hostname)) // MTU vicon tracker
{
/* Note, orient has not been transposed/inverted yet. Doing
* orient*offset will effectively effectively be rotating the
* camera---not the world. */
if(strcmp(viewmat_vrpn_obj, "DK2") == 0)
{
float offsetVicon[16];
mat4f_identity(offsetVicon);
mat4f_rotateAxis_new(offsetVicon, 90, 1,0,0);
mat4f_mult_mat4f_new(orient, orient, offsetVicon);
}
if(strcmp(viewmat_vrpn_obj, "DSight") == 0)
{
float offsetVicon1[16];
mat4f_identity(offsetVicon1);
mat4f_rotateAxis_new(offsetVicon1, 90, 1,0,0);
float offsetVicon2[16];
mat4f_identity(offsetVicon2);
mat4f_rotateAxis_new(offsetVicon2, 180, 0,1,0);
// orient = orient * offsetVicon1 * offsetVicon2
mat4f_mult_mat4f_many(orient, orient, offsetVicon1, offsetVicon2, NULL);
}
}
}
void get_model_matrix(float result[16])
{
mat4f_identity(result);
if(FIT_TO_VIEW_AND_ROTATE == 0)
{
/* Translate the model to where we were asked to put it */
float translate[16];
mat4f_translateVec_new(translate, placeToPutModel);
/* Do inches to meters conversion if we are asked to. */
float scale[16];
mat4f_identity(scale);
if(INCHES_TO_METERS)
{
float inchesToMeters=1/39.3701;
mat4f_scale_new(scale, inchesToMeters, inchesToMeters, inchesToMeters);
}
mat4f_mult_mat4f_new(result, translate, scale);
return;
}
/* Change angle for animation. */
int count = glutGet(GLUT_ELAPSED_TIME) % 10000; // get a counter that repeats every 10 seconds
/* Animate the model if there is animation information available. */
kuhl_update_model_file_ogl3(modelFilename, 0, count/1000.0);
dgr_setget("count", &count, sizeof(int));
/* Calculate the width/height/depth of the bounding box and
* determine which one of the three is the largest. Then, scale
* the scene by 1/(largest value) to ensure that it fits in our
* view frustum. */
float bb_min[3], bb_max[3], bb_center[3];
kuhl_model_bounding_box(modelFilename, bb_min, bb_max, bb_center);
#define mymax(a,b) (a>b?a:b)
float tmp;
tmp = bb_max[0] - bb_min[0];
tmp = mymax(bb_max[1] - bb_min[1], tmp);
tmp = mymax(bb_max[2] - bb_min[2], tmp);
tmp = 1.f / tmp;
#undef mymax
float scaleBoundBox[16], moveToOrigin[16], moveToLookPoint[16];
mat4f_translate_new(moveToOrigin, -bb_center[0], -bb_center[1], -bb_center[2]); // move to origin
// printf("Scaling by factor %f\n", tmp);
mat4f_scale_new(scaleBoundBox, tmp, tmp, tmp); // scale model based on bounding box size
mat4f_translateVec_new(moveToLookPoint, placeToPutModel);
mat4f_mult_mat4f_new(result, moveToOrigin, result);
mat4f_mult_mat4f_new(result, scaleBoundBox, result);
mat4f_mult_mat4f_new(result, moveToLookPoint, result);
}
void display()
{
/* If we are using DGR, send or receive data to keep multiple
* processes/computers synchronized. */
dgr_update();
/* Get current frames per second calculations. */
float fps = kuhl_getfps(&fps_state);
if(dgr_is_enabled() == 0 || dgr_is_master())
{
// If DGR is being used, only display dgr counter if we are
// the master process.
// Check if FPS value was just updated by kuhl_getfps()
if(fps_state.frame == 0)
{
char label[1024];
snprintf(label, 1024, "FPS: %0.1f", fps);
/* Delete old label if it exists */
if(fpsLabel != 0)
glDeleteTextures(1, &fpsLabel);
/* Make a new label */
float labelColor[3] = { 1,1,1 };
float labelBg[4] = { 0,0,0,.3 };
/* Change the last parameter (point size) to adjust the
* size of the texture that the text is rendered in to. */
fpsLabelAspectRatio = kuhl_make_label(label,
&fpsLabel,
labelColor, labelBg, 24);
if(fpsLabel != 0)
kuhl_geometry_texture(&labelQuad, fpsLabel, "tex", 1);
}
}
/* Ensure the slaves use the same render style as the master
* process. */
dgr_setget("style", &renderStyle, sizeof(int));
/* Render the scene once for each viewport. Frequently one
* viewport will fill the entire screen. However, this loop will
* run twice for HMDs (once for the left eye and once for the
* right. */
viewmat_begin_frame();
for(int viewportID=0; viewportID<viewmat_num_viewports(); viewportID++)
{
viewmat_begin_eye(viewportID);
/* Where is the viewport that we are drawing onto and what is its size? */
int viewport[4]; // x,y of lower left corner, width, height
viewmat_get_viewport(viewport, viewportID);
glViewport(viewport[0], viewport[1], viewport[2], viewport[3]);
/* Clear the current viewport. Without glScissor(), glClear()
* clears the entire screen. We could call glClear() before
* this viewport loop---but on order for all variations of
* this code to work (Oculus support, etc), we can only draw
* after viewmat_begin_eye(). */
glScissor(viewport[0], viewport[1], viewport[2], viewport[3]);
glEnable(GL_SCISSOR_TEST);
glClearColor(.2,.2,.2,0); // set clear color to grey
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
glDisable(GL_SCISSOR_TEST);
glEnable(GL_DEPTH_TEST); // turn on depth testing
kuhl_errorcheck();
/* Turn on blending (note, if you are using transparent textures,
the transparency may not look correct unless you draw further
items before closer items.). */
glEnable(GL_BLEND);
glBlendEquationSeparate(GL_FUNC_ADD, GL_FUNC_ADD);
glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ZERO);
/* Get the view or camera matrix; update the frustum values if needed. */
float viewMat[16], perspective[16];
viewmat_get(viewMat, perspective, viewportID);
glUseProgram(program);
kuhl_errorcheck();
/* Send the perspective projection matrix to the vertex program. */
glUniformMatrix4fv(kuhl_get_uniform("Projection"),
1, // number of 4x4 float matrices
0, // transpose
perspective); // value
float modelMat[16];
get_model_matrix(modelMat);
float modelview[16];
mat4f_mult_mat4f_new(modelview, viewMat, modelMat); // modelview = view * model
/* Send the modelview matrix to the vertex program. */
glUniformMatrix4fv(kuhl_get_uniform("ModelView"),
1, // number of 4x4 float matrices
0, // transpose
modelview); // value
glUniform1i(kuhl_get_uniform("renderStyle"), renderStyle);
// Copy far plane value into vertex program so we can render depth buffer.
float f[6]; // left, right, bottom, top, near>0, far>0
projmat_get_frustum(f, viewport[2], viewport[3]);
glUniform1f(kuhl_get_uniform("farPlane"), f[5]);
kuhl_errorcheck();
kuhl_geometry_draw(modelgeom); /* Draw the model */
kuhl_errorcheck();
if(showOrigin)
{
/* Save current line width */
GLfloat origLineWidth;
glGetFloatv(GL_LINE_WIDTH, &origLineWidth);
glLineWidth(4); // make lines thick
/* Object coordinate system origin */
kuhl_geometry_draw(origingeom); /* Draw the origin marker */
/* World coordinate origin */
mat4f_copy(modelview, viewMat);
glUniformMatrix4fv(kuhl_get_uniform("ModelView"),
1, // number of 4x4 float matrices
0, // transpose
modelview); // value
kuhl_geometry_draw(origingeom); /* Draw the origin marker */
/* Restore line width */
glLineWidth(origLineWidth);
}
if(dgr_is_enabled() == 0 || dgr_is_master())
{
/* The shape of the frames per second quad depends on the
* aspect ratio of the label texture and the aspect ratio of
* the window (because we are placing the quad in normalized
* device coordinates). */
int windowWidth, windowHeight;
viewmat_window_size(&windowWidth, &windowHeight);
float windowAspect = windowWidth / (float)windowHeight;
float stretchLabel[16];
mat4f_scale_new(stretchLabel, 1/8.0 * fpsLabelAspectRatio / windowAspect, 1/8.0, 1);
/* Position label in the upper left corner of the screen */
float transLabel[16];
mat4f_translate_new(transLabel, -.9, .8, 0);
mat4f_mult_mat4f_new(modelview, transLabel, stretchLabel);
glUniformMatrix4fv(kuhl_get_uniform("ModelView"), 1, 0, modelview);
/* Make sure we don't use a projection matrix */
float identity[16];
mat4f_identity(identity);
glUniformMatrix4fv(kuhl_get_uniform("Projection"), 1, 0, identity);
/* Don't use depth testing and make sure we use the texture
* rendering style */
glDisable(GL_DEPTH_TEST);
glUniform1i(kuhl_get_uniform("renderStyle"), 1);
kuhl_geometry_draw(&labelQuad); /* Draw the quad */
glEnable(GL_DEPTH_TEST);
kuhl_errorcheck();
}
glUseProgram(0); // stop using a GLSL program.
} // finish viewport loop
viewmat_end_frame();
/* Update the model for the next frame based on the time. We
* convert the time to seconds and then use mod to cause the
* animation to repeat. */
int time = glutGet(GLUT_ELAPSED_TIME);
dgr_setget("time", &time, sizeof(int));
kuhl_update_model(modelgeom, 0, ((time%10000)/1000.0));
/* Check for errors. If there are errors, consider adding more
* calls to kuhl_errorcheck() in your code. */
kuhl_errorcheck();
//kuhl_video_record("videoout", 30);
/* Ask GLUT to call display() again. We shouldn't call display()
* ourselves recursively because it will not leave time for GLUT
* to call other callback functions for when a key is pressed, the
* window is resized, etc. */
glutPostRedisplay();
}
/* Called by GLUT whenever the window needs to be redrawn. This
* function should not be called directly by the programmer. Instead,
* we can call glutPostRedisplay() to request that GLUT call display()
* at some point. */
void display()
{
/* If we are using DGR, send or receive data to keep multiple
* processes/computers synchronized. */
dgr_update();
/* Render the scene once for each viewport. Frequently one
* viewport will fill the entire screen. However, this loop will
* run twice for HMDs (once for the left eye and once for the
* right.) */
viewmat_begin_frame();
for(int viewportID=0; viewportID<viewmat_num_viewports(); viewportID++)
{
viewmat_begin_eye(viewportID);
/* Where is the viewport that we are drawing onto and what is its size? */
int viewport[4]; // x,y of lower left corner, width, height
viewmat_get_viewport(viewport, viewportID);
glViewport(viewport[0], viewport[1], viewport[2], viewport[3]);
/* Clear the current viewport. Without glScissor(), glClear()
* clears the entire screen. We could call glClear() before
* this viewport loop---but on order for all variations of
* this code to work (Oculus support, etc), we can only draw
* after viewmat_begin_eye(). */
glScissor(viewport[0], viewport[1], viewport[2], viewport[3]);
glEnable(GL_SCISSOR_TEST);
glClearColor(.2,.2,.2,0); // set clear color to grey
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT|GL_STENCIL_BUFFER_BIT);
glDisable(GL_SCISSOR_TEST);
glEnable(GL_DEPTH_TEST); // turn on depth testing
kuhl_errorcheck();
/* Get the view or camera matrix; update the frustum values if needed. */
float viewMat[16], perspective[16];
viewmat_get(viewMat, perspective, viewportID);
/* Calculate an angle to rotate the
* object. glutGet(GLUT_ELAPSED_TIME) is the number of
* milliseconds since glutInit() was called. */
int count = glutGet(GLUT_ELAPSED_TIME) % 10000; // get a counter that repeats every 10 seconds
float angle = count / 10000.0 * 360; // rotate 360 degrees every 10 seconds
/* Make sure all computers/processes use the same angle */
dgr_setget("angle", &angle, sizeof(GLfloat));
/* Create a 4x4 rotation matrix based on the angle we computed. */
float rotateMat[16];
mat4f_rotateAxis_new(rotateMat, angle, 0,1,0);
/* Create a scale matrix. */
float scaleMatrix[16];
mat4f_scale_new(scaleMatrix, 3, 3, 3);
// Modelview = (viewMatrix * scaleMatrix) * rotationMatrix
float modelview[16];
mat4f_mult_mat4f_new(modelview, viewMat, scaleMatrix);
mat4f_mult_mat4f_new(modelview, modelview, rotateMat);
kuhl_errorcheck();
glUseProgram(program);
kuhl_errorcheck();
/* Send the perspective projection matrix to the vertex program. */
glUniformMatrix4fv(kuhl_get_uniform("Projection"),
1, // number of 4x4 float matrices
0, // transpose
perspective); // value
/* Send the modelview matrix to the vertex program. */
glUniformMatrix4fv(kuhl_get_uniform("ModelView"),
1, // number of 4x4 float matrices
0, // transpose
modelview); // value
kuhl_errorcheck();
/* Draw the geometry using the matrices that we sent to the
* vertex programs immediately above. Use the stencil buffer
* to keep track of which object appears on top. */
if(viewportID == 0)
glEnable(GL_STENCIL_TEST);
glStencilOp(GL_KEEP, GL_KEEP, GL_REPLACE);
glStencilFunc(GL_ALWAYS, 1, -1);
kuhl_geometry_draw(&triangle);
glStencilFunc(GL_ALWAYS, 2, -1);
kuhl_geometry_draw(&quad);
glDisable(GL_STENCIL_TEST);
/* If we have multiple viewports, only draw cursor in the
* first viewport. */
if(viewportID == 0)
{
/* Draw the cursor in normalized device coordinates. Don't
* use any matrices. */
float identity[16];
mat4f_identity(identity);
glUniformMatrix4fv(kuhl_get_uniform("Projection"),
1, 0, identity);
glUniformMatrix4fv(kuhl_get_uniform("ModelView"),
1, 0, identity);
/* Disable depth testing so the cursor isn't occluded by
* anything. */
glDisable(GL_DEPTH_TEST);
kuhl_geometry_draw(&cursor);
glEnable(GL_DEPTH_TEST);
/* When we render images on the Oculus, we are rendering
* into a multisampled framebuffer object, and we can't
* read from the multisample FBO until we have blitted it
* into a normal FBO. Here, we get the blitted FBO for the
* *previous* frame. */
GLint fb =viewmat_get_blitted_framebuffer(viewportID);
glBindFramebuffer(GL_FRAMEBUFFER, fb);
GLuint stencilVal = 0;
kuhl_errorcheck();
glReadPixels(viewport[0]+viewport[2]/2, viewport[1]+viewport[3]/2,
1,1, // get data for 1x1 area (i.e., a pixel)
GL_STENCIL_INDEX, // query the stencil buffer
GL_UNSIGNED_INT,
&stencilVal);
kuhl_errorcheck();
if(stencilVal == 1)
printf("Cursor is on triangle.\n");
else if(stencilVal == 2)
printf("Cursor is on quad.\n");
else
printf("Cursor isn't on anything.\n");
}
glUseProgram(0); // stop using a GLSL program.
} // finish viewport loop
viewmat_end_frame();
/* Check for errors. If there are errors, consider adding more
* calls to kuhl_errorcheck() in your code. */
kuhl_errorcheck();
/* Ask GLUT to call display() again. We shouldn't call display()
* ourselves recursively because it will not leave time for GLUT
* to call other callback functions for when a key is pressed, the
* window is resized, etc. */
glutPostRedisplay();
}
/** Uses the VRPN library to get the position and orientation of a
* tracked object.
*
* @param object The name of the object being tracked.
*
* @param hostname The IP address or hostname of the VRPN server or
* tracking system computer. If hostname is set to NULL, the
* ~/.vrpn-server file is consulted.
*
* @param pos An array to be filled in with the position information
* for the tracked object. If we are unable to track the object, a
* message may be printed and pos will be set to a fixed value.
*
* @param orient An array to be filled in with the orientation matrix
* for the tracked object. The orientation matrix is in row-major
* order can be used with OpenGL. If the tracking system is moving an
* object around on the screen, this matrix can be used directly. If
* the tracking system is moving the OpenGL camera, this matrix may
* need to be inverted. If we are unable to track the object, a
* message may be printed and orient will be set to the identity
* matrix.
*
* @return 1 if we returned data from the tracker. 0 if there was
* problems connecting to the tracker.
*/
int vrpn_get(const char *object, const char *hostname, float pos[3], float orient[16])
{
/* Set to default values */
vec3f_set(pos, 10000,10000,10000);
mat4f_identity(orient);
#ifdef MISSING_VRPN
printf("You are missing VRPN support.\n");
return 0;
#else
if(object == NULL || strlen(object) == 0)
{
msg(WARNING, "Empty or NULL object name was passed into this function.\n");
return 0;
}
if(hostname != NULL && strlen(hostname) == 0)
{
msg(WARNING, "Hostname is an empty string.\n");
return 0;
}
/* Construct an object@hostname string. */
std::string hostnamecpp;
std::string objectcpp;
if(hostname == NULL)
{
char *hostnameInFile = vrpn_default_host();
if(hostnameInFile)
hostnamecpp = hostnameInFile;
else
{
msg(ERROR, "Failed to find hostname of VRPN server.\n");
exit(EXIT_FAILURE);
}
}
else
hostnamecpp = hostname;
objectcpp = object;
std::string fullname = objectcpp + "@" + hostnamecpp;
/* Check if we have a tracker object for that string in our map. */
if(nameToTracker.count(fullname))
{
/* If we already have a tracker object, ask it to run the main
* loop (and therefore call our handle_tracker() function if
* there is new data). */
nameToTracker[fullname]->mainloop();
/* If our callback has been called, get the callback object
* and get the data out of it. */
if(nameToCallbackData.count(fullname))
{
vrpn_TRACKERCB t = nameToCallbackData[fullname];
float pos4[4];
for(int i=0; i<3; i++)
pos4[i] = t.pos[i];
pos4[3]=1;
double orientd[16];
// Convert quaternion into orientation matrix.
q_to_ogl_matrix(orientd, t.quat);
for(int i=0; i<16; i++)
orient[i] = (float) orientd[i];
/* VICON in the MTU IVS lab is typically calibrated so that:
* X = points to the right (while facing screen)
* Y = points into the screen
* Z = up
* (left-handed coordinate system)
*
* PPT is typically calibrated so that:
* X = the points to the wall that has two closets at both corners
* Y = up
* Z = points to the door
* (right-handed coordinate system)
*
* By default, OpenGL assumes that:
* X = points to the right (while facing screen in the IVS lab)
* Y = up
* Z = points OUT of the screen (i.e., -Z points into the screen in te IVS lab)
* (right-handed coordinate system)
*
* Below, we convert the position and orientation
* information into the OpenGL convention.
*/
if(strlen(hostnamecpp.c_str()) > 14 && strncmp(hostnamecpp.c_str(), "tcp://141.219.", 14) == 0) // MTU vicon tracker
{
float viconTransform[16] = { 1,0,0,0, // column major order!
0,0,-1,0,
0,1,0,0,
0,0,0,1 };
mat4f_mult_mat4f_new(orient, viconTransform, orient);
mat4f_mult_vec4f_new(pos4, viconTransform, pos4);
vec3f_copy(pos,pos4);
return 1; // we successfully collected some data
}
else // Non-Vicon tracker
{
/* Don't transform other tracking systems */
// orient is already filled in
vec3f_copy(pos, pos4);
return 1; // we successfully collected some data
}
}
}
else
{
/* If this is our first time, create a tracker for the object@hostname string, register the callback handler. */
msg(INFO, "Connecting to VRPN server: %s\n", hostnamecpp.c_str());
// If we are making a TCP connection and the server isn't up, the following function call may hang for a long time
vrpn_Connection *connection = vrpn_get_connection_by_name(hostnamecpp.c_str());
/* Wait for a bit to see if we can connect. Sometimes we don't immediately connect! */
for(int i=0; i<1000 && !connection->connected(); i++)
{
usleep(1000); // 1000 microseconds * 1000 = up to 1 second of waiting.
connection->mainloop();
}
/* If connection failed, exit. */
if(!connection->connected())
{
delete connection;
msg(ERROR, "Failed to connect to tracker: %s\n", fullname.c_str());
return 0;
}
vrpn_Tracker_Remote *tkr = new vrpn_Tracker_Remote(fullname.c_str(), connection);
nameToTracker[fullname] = tkr;
tkr->register_change_handler((void*) fullname.c_str(), handle_tracker);
kuhl_getfps_init(&fps_state);
kalman_initialize(&kalman, 0.1, 0.1);
}
return 0;
#endif
}
/** Get view and projection matrices appropriate for the Oculus HMD */
static void viewmat_get_hmd_oculus(float viewmatrix[16], float projmatrix[16], int viewportID)
{
#ifndef MISSING_OVR
/* Oculus recommends the order that we should render eyes. We
* assume that smaller viewportIDs are rendered first. So, we need
* to map the viewportIDs to the specific Oculus HMD eye. The
* "eye" variable will be set to either ovrEye_Left (if we are
* rendering the left eye) or ovrEye_Right (if we are rendering
* the right eye). */
ovrEyeType eye = hmd->EyeRenderOrder[viewportID];
/* Oculus doesn't provide us with easy access to the view
* frustum information. We get the projection matrix directly
* from libovr. */
ovrMatrix4f ovrpersp = ovrMatrix4f_Projection(hmd->DefaultEyeFov[eye], 0.5, 500, 1);
mat4f_setRow(projmatrix, &(ovrpersp.M[0][0]), 0);
mat4f_setRow(projmatrix, &(ovrpersp.M[1][0]), 1);
mat4f_setRow(projmatrix, &(ovrpersp.M[2][0]), 2);
mat4f_setRow(projmatrix, &(ovrpersp.M[3][0]), 3);
float offsetMat[16], rotMat[16], posMat[16], initPosMat[16];
mat4f_identity(offsetMat); // Viewpoint offset (IPD, etc);
mat4f_identity(rotMat); // tracking system rotation
mat4f_identity(posMat); // tracking system position
mat4f_identity(initPosMat); // camera starting location
/* Construct posMat and rotMat matrices which indicate the
* position and orientation of the HMD. */
if(viewmat_vrpn_obj) // get position from VRPN
{
/* Get the offset for the left and right eyes from
* Oculus. If you are using a separate tracking system, you
* may also want to apply an offset here between the tracked
* point and the eye location. */
mat4f_translate_new(offsetMat,
eye_rdesc[eye].HmdToEyeViewOffset.x, // left & right IPD offset
eye_rdesc[eye].HmdToEyeViewOffset.y, // vertical offset
eye_rdesc[eye].HmdToEyeViewOffset.z); // forward/back offset
float pos[3] = { 0,0,0 };
vrpn_get(viewmat_vrpn_obj, NULL, pos, rotMat);
mat4f_translate_new(posMat, -pos[0], -pos[1], -pos[2]); // position
viewmat_fix_rotation(rotMat);
}
else // get position from Oculus tracker
{
pose[eye] = ovrHmd_GetHmdPosePerEye(hmd, eye);
mat4f_translate_new(posMat, // position (includes IPD offset)
-pose[eye].Position.x,
-pose[eye].Position.y,
-pose[eye].Position.z);
mat4f_rotateQuat_new(rotMat, // rotation
pose[eye].Orientation.x,
pose[eye].Orientation.y,
pose[eye].Orientation.z,
pose[eye].Orientation.w);
// Starting point:
// Translate the world based on the initial camera position
// specified in viewmat_init(). You may choose to initialize the
// camera position with y=1.5 meters to approximate a normal
// standing eyeheight.
float initPosVec[3];
vec3f_scalarMult_new(initPosVec, oculus_initialPos, -1.0f);
mat4f_translateVec_new(initPosMat, initPosVec);
// TODO: Could also get eyeheight via ovrHmd_GetFloat(hmd, OVR_KEY_EYE_HEIGHT, 1.65)
}
mat4f_transpose(rotMat); /* orientation sensor rotates camera, not world */
// viewmatrix = offsetMat * rotMat * posMat * initposmat
mat4f_mult_mat4f_new(viewmatrix, offsetMat, rotMat); // offset is identity if we are using Oculus tracker
mat4f_mult_mat4f_new(viewmatrix, viewmatrix, posMat);
mat4f_mult_mat4f_new(viewmatrix, viewmatrix, initPosMat);
if(0)
{
printf("ViewportID=%d; eye=%s\n", viewportID, eye == ovrEye_Left ? "left" : "right");
printf("Eye offset according to OVR (only used if VRPN is used): ");
mat4f_print(offsetMat);
printf("Rotation sensing (from OVR or VRPN): ");
mat4f_print(rotMat);
printf("Position tracking (from OVR or VRPN): ");
mat4f_print(posMat);
printf("Initial position (from set in viewmat_init()): ");
mat4f_print(initPosMat);
printf("Final view matrix: ");
mat4f_print(viewmatrix);
}
#else
/* We shouldn't ever get here, but we'll generate a generic view
* and projection matrix just in case... */
mat4f_lookat_new(viewmatrix,
0,1.55,0,
0,1.55,-1,
0,1,0);
mat4f_perspective_new(projmatrix, 50, 1, 0.5, 500);
#endif
}
