With C++

C++ has lack of everything useful, you won't find local functions for example. But I really miss Pascal with statement. I know people say that would confuse programmer or even compiler. Wait! Pascal programmers were not confused, Pascal compilers were able to deal with this. Moreover, C++ programmers are not confused with tons of nested name spaces, crazy visibility rules and other odds.

Here is a snippet from my program:

for (unsigned i=0; i < data.measure_dist.size(); i++)
  if (data.measure_dist[i].active)
     find_crosspoints(
         data.measure_dist[i].point_1,
         data.measure_dist[i].point_2,
         outline,
         data.measure_dist[i].crosspoints
     );

Using with would make this much clearer:

for (unsigned i=0; i < data.measure_dist.size(); i++)
  with (data.measure_dist[i]) {
     if (active)
         find_crosspoints(point_1, point_2, outline, crosspoints);
  }

Does anybody confused about this code? Does anybody don't know what above code do? I don't think so.

Lets continue. With could also accept more complex syntax and allow temporary rename different entities. This (inefficient!) code finds all intersection between two sets of segments:

double u, v; // parameters, lerp(A, B, u) = A + u*(B-A)
for (int i=0; i < data.points.inner.size() - 1; i++)
  for (int j=0; j < data.points.outer.size() - 1; j++) {
      bool b = intersection(
          data.outline.inner[i],
          data.outline.inner[i+1],
          data.outline.outer[j],
          data.outline.outer[j+1],
          u, v);

      if (b)
          crosspoints.add(lerp(data.outline.inner[i], data.outline.inner[i+1], u));
  }

Now compare with following code:

double u, v;
with (data.points) {
  with (inner as A, outer as B) {
      for (int i=0; i < A.size() - 1; i++)
          for (int j=0; j < B.size() - 1; j++)
              if (intersection(A[i], A[i+1], B[i], B[i+1]))
                  crosspoints.add(lerp(A[i], A[i+1], u));
      }
}

Code is easier, cleaner, compacted. In next posts I will show some other ideas.

demoscene.tv

For a years I was big fan of demoscene. When I was young, demos and intros (some watched over and over, like "Jizz" by TBL) pushed me to learn many new things; moreover I still like to listen demoscene music; for example tracks from music disc "Ambrozia" released by group Pulse around 10 years ago still sound nice.

Now youtube is full of old and new demos uploaded by Good People. But on the net there are Much Better Good People, who created http://demoscene.tv - you can watch demos in high quality, yeah. BTW I love "Photon" by Purple.