// Function provided by Joe Dowsett, 2014
double DrawProjGroup::calculateAutomaticScale() const
{
TechDraw::DrawPage *page = getPage();
if (page == NULL)
throw Base::Exception("No page is assigned to this feature");
if(!page->hasValidTemplate())
throw Base::Exception("Page template isn't valid");
DrawProjGroupItem *viewPtrs[10];
arrangeViewPointers(viewPtrs);
double width, height;
minimumBbViews(viewPtrs, width, height);
// C++ Standard says casting bool to int gives 0 or 1
int numVertSpaces = (viewPtrs[0] || viewPtrs[3] || viewPtrs[7]) +
(viewPtrs[2] || viewPtrs[5] || viewPtrs[9]) +
(viewPtrs[6] != NULL);
int numHorizSpaces = (viewPtrs[0] || viewPtrs[1] || viewPtrs[2]) +
(viewPtrs[7] || viewPtrs[8] || viewPtrs[9]);
double availableX = page->getPageWidth() - spacingX.getValue() * (numVertSpaces + 1);
double availableY = page->getPageHeight() - spacingY.getValue() * (numHorizSpaces + 1);
double scale_x = availableX / width;
double scale_y = availableY / height;
float working_scale = std::min(scale_x, scale_y);
//which gives the largest scale for which the min_space requirements can be met, but we want a 'sensible' scale, rather than 0.28457239...
//eg if working_scale = 0.115, then we want to use 0.1, similarly 7.65 -> 5, and 76.5 -> 50
float exponent = std::floor(std::log10(working_scale)); //if working_scale = a * 10^b, what is b?
working_scale *= std::pow(10, -exponent); //now find what 'a' is.
float valid_scales[2][8] = {{1.0, 1.25, 2.0, 2.5, 3.75, 5.0, 7.5, 10.0}, //equate to 1:10, 1:8, 1:5, 1:4, 3:8, 1:2, 3:4, 1:1
{1.0, 1.5 , 2.0, 3.0, 4.0 , 5.0, 8.0, 10.0}}; //equate to 1:1, 3:2, 2:1, 3:1, 4:1, 5:1, 8:1, 10:1
int i = 7;
while (valid_scales[(exponent >= 0)][i] > working_scale) //choose closest value smaller than 'a' from list.
i -= 1; //choosing top list if exponent -ve, bottom list for +ve exponent
//now have the appropriate scale, reapply the *10^b
return valid_scales[(exponent >= 0)][i] * pow(10, exponent);
}
App::DocumentObjectExecReturn *DrawView::execute(void)
{
TechDraw::DrawPage *page = findParentPage();
if(page) {
if (ScaleType.isValue("Document")) {
if(std::abs(page->Scale.getValue() - Scale.getValue()) > FLT_EPSILON) {
Scale.setValue(page->Scale.getValue());
}
} else if (ScaleType.isValue("Automatic")) {
//check fit. if too big, rescale
if (!checkFit(page)) {
double newScale = autoScale(page->getPageWidth(),page->getPageHeight());
if(std::abs(newScale - Scale.getValue()) > FLT_EPSILON) { //stops onChanged/execute loop
Scale.setValue(newScale);
}
}
}
}
return App::DocumentObject::execute();
}