//-----------------------------------------------------------------------------
// pick() -- Perform for select/pick operation; returns the selected (picked)
// graphic or zero(0) if nothing was selected.
//
// 1) When item == 0, returns nearest (by depth buffer) selected entry.
// 2) When item < 0, returns furthest (by depth buffer) selected entry.
// 3) When item > 0, returns the item'th selected entry or the first entry if
// there are less than 'item' entries
// 4) Returns zero(0) when there are no entries in the select buffer or if the
// Graphic for the select ID is not found.
//-----------------------------------------------------------------------------
BasicGL::Graphic* GlutDisplay::pick(const int item)
{
GLint viewport[4];
glGetIntegerv(GL_VIEWPORT,viewport);
// make sure we are starting at 0, 0
int xm = 0, ym = 0;
getMouse(&xm,&ym);
int x = xm;
int y = viewport[3] - ym;
glMatrixMode(GL_PROJECTION);
glPushMatrix();
glLoadIdentity();
gluPickMatrix(x, y, getPickWidth(), getPickHeight(), viewport);
// Get our ortho parameters
GLdouble oLeft(0), oRight(0), oBottom(0), oTop(0), oNear(0), oFar(0);
getOrtho(oLeft, oRight, oBottom, oTop, oNear, oFar);
glOrtho(oLeft, oRight, oBottom, oTop, oNear, oFar);
glMatrixMode(GL_MODELVIEW);
if (getDisplayOrientation() != NORMAL) {
glPushMatrix();
if (getDisplayOrientation() == CW90)
glRotated(-90.0, 0.0, 0.0, 1.0);
else if (getDisplayOrientation() == CCW90)
glRotated(90.0, 0.0, 0.0, 1.0);
else
glRotated(180.0, 0.0, 0.0, 1.0);
}
static const unsigned int MAX_BUFF_SIZE = 1024;
GLuint sbuff[MAX_BUFF_SIZE];
clearSelectBuffer(sbuff,MAX_BUFF_SIZE);
glSelectBuffer(MAX_BUFF_SIZE, sbuff);
glRenderMode(GL_SELECT);
glInitNames();
draw();
GLint hits = glRenderMode(GL_RENDER);
if (getDisplayOrientation() != NORMAL) glPopMatrix();
Graphic* selected = findSelected(hits, sbuff, item);
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glMatrixMode(GL_MODELVIEW);
return selected;
}
bool GraphicsManager::unproject(float x, float y,
float &x1, float &y1, float &z1,
float &x2, float &y2, float &z2) const {
try {
// Generate the inverse of the model matrix
Common::TransformationMatrix model;
float cPos[3];
float cOrient[3];
memcpy(cPos , CameraMan.getPosition (), 3 * sizeof(float));
memcpy(cOrient, CameraMan.getOrientation(), 3 * sizeof(float));
// Apply camera position
model.translate(cPos[0], cPos[1], -cPos[2]);
// Apply camera orientation
model.rotate( cOrient[2], 0.0f, 0.0f, 1.0f);
model.rotate(-cOrient[1], 0.0f, 1.0f, 0.0f);
model.rotate( cOrient[0], 1.0f, 0.0f, 0.0f);
// Multiply with the inverse of our projection matrix
model *= _projectionInv;
// Coordinates at the near and far clipping planes
Common::Vector3 coordsNear, coordsFar;
if (_projectType == kProjectTypePerspective) {
/* With a perspective projection, the viewport runs from -1.0 to 0.0
* on the x and y axes, and the clipping planes are at 0.0 and 1.0. */
const float view[4] = { 0.0f, 0.0f, (float) _width, (float) _height };
const float zNear = 0.0f;
const float zFar = 1.0f;
coordsNear._x = ((2 * (x - view[0])) / (view[2])) - 1.0f;
coordsNear._y = ((2 * (y - view[1])) / (view[3])) - 1.0f;
coordsNear._z = (2 * zNear) - 1.0f;
coordsNear._w = 1.0f;
coordsFar._x = ((2 * (x - view[0])) / (view[2])) - 1.0f;
coordsFar._y = ((2 * (y - view[1])) / (view[3])) - 1.0f;
coordsFar._z = (2 * zFar) - 1.0f;
coordsFar._w = 1.0f;
} else if (_projectType == kProjectTypeOrthogonal) {
/* With an orthogonal projection, the viewport runs from 0.0 to width
* on the x axis and from 0.0 to height on the y axis (which already
* matches the coordinates we were given), and the clipping planes are
* at -clipNear and -clipFar. */
coordsNear._x = x;
coordsNear._y = y;
coordsNear._z = -_clipNear;
coordsNear._w = 1.0f;
coordsFar._x = x;
coordsFar._y = y;
coordsFar._z = -_clipFar;
coordsFar._w = 1.0f;
}
// Unproject
Common::Vector3 oNear(model * coordsNear);
Common::Vector3 oFar (model * coordsFar );
if ((oNear._w == 0.0f) || (oFar._w == 0.0f))
return false; // TODO: check for close to 0.0f, not exactly 0.0f.
// And return the values
oNear._w = 1.0f / oNear._w;
x1 = oNear._x * oNear._w;
y1 = oNear._y * oNear._w;
z1 = oNear._z * oNear._w;
oFar._w = 1.0f / oFar._w;
x2 = oFar._x * oFar._w;
y2 = oFar._y * oFar._w;
z2 = oFar._z * oFar._w;
} catch (Common::Exception &e) {
Common::printException(e, "WARNING: ");
return false;
} catch (...) {
return false;
}
return true;
}
bool GraphicsManager::unproject(float x, float y,
float &x1, float &y1, float &z1,
float &x2, float &y2, float &z2) const {
try {
// Generate the inverse of the model matrix
Common::TransformationMatrix model;
float cPos[3];
float cOrient[3];
CameraMan.lock();
memcpy(cPos , CameraMan.getPosition (), 3 * sizeof(float));
memcpy(cOrient, CameraMan.getOrientation(), 3 * sizeof(float));
CameraMan.unlock();
// Apply camera position
model.translate(cPos[0], cPos[1], -cPos[2]);
// Apply camera orientation
model.rotate( cOrient[2], 0.0, 0.0, 1.0);
model.rotate(-cOrient[1], 0.0, 1.0, 0.0);
model.rotate( cOrient[0], 1.0, 0.0, 0.0);
// Multiply with the inverse of our projection matrix
model *= _projectionInv;
// Viewport coordinates
float view[4];
view[0] = 0.0;
view[1] = 0.0;
view[2] = _screen->w;
view[3] = _screen->h;
float zNear = 0.0;
float zFar = 1.0;
// Generate a matrix for the coordinates at the near plane
Common::Matrix coordsNear(4, 1);
coordsNear(0, 0) = ((2 * (x - view[0])) / (view[2])) - 1.0;
coordsNear(1, 0) = ((2 * (y - view[1])) / (view[3])) - 1.0;
coordsNear(2, 0) = (2 * zNear) - 1.0;
coordsNear(3, 0) = 1.0;
// Generate a matrix for the coordinates at the far plane
Common::Matrix coordsFar(4, 1);
coordsFar(0, 0) = ((2 * (x - view[0])) / (view[2])) - 1.0;
coordsFar(1, 0) = ((2 * (y - view[1])) / (view[3])) - 1.0;
coordsFar(2, 0) = (2 * zFar) - 1.0;
coordsFar(3, 0) = 1.0;
// Unproject
Common::Matrix oNear(model * coordsNear);
Common::Matrix oFar (model * coordsFar );
if ((oNear(3, 0) == 0.0) || (oNear(3, 0) == 0.0))
return false;
// And return the values
oNear(3, 0) = 1.0 / oNear(3, 0);
x1 = oNear(0, 0) * oNear(3, 0);
y1 = oNear(1, 0) * oNear(3, 0);
z1 = oNear(2, 0) * oNear(3, 0);
oFar(3, 0) = 1.0 / oFar(3, 0);
x2 = oFar(0, 0) * oFar(3, 0);
y2 = oFar(1, 0) * oFar(3, 0);
z2 = oFar(2, 0) * oFar(3, 0);
} catch (Common::Exception &e) {
Common::printException(e, "WARNING: ");
return false;
} catch (...) {
return false;
}
return true;
}
