We all know what jazz is, right?

That music characterized by swing (sometimes) and lots of sevenths

Discuss your experiences with jazz here (favorite tunes, if you've been in jazz band, etc)



Why? I feel as if jazz is a lost genre of music, there is only 1 jazz station in Atlanta anymore, and most of the songs it plays are from the 70s and before.

I noticed that on Cemetech and Ti-Planet there are usergroups that you can be a part of. Not in the sense of moderators and such, but in the sense of groups of users.

Is there any way we can add that to the site?

Line clipping? I thought that that is a problem being worked on by Runer112 for future versions?

Well, yes, but here's a temporary fix, using trig!

To all those who may spot any error in my trig: please tell me. I'll try to fix it.



Inspiration:

I saw god's (leafy's) Super Hexagon port, and I saw a problem that he listed: The line clipping. I thought to myself: how do I solve this? The answer is by using trig!

Just to show you I'm not crazy: here are some screenies for a very incomplete Super Hexagon engine (I will not continue after this point because I just made it to solve a problem):



Axe trig background:

Trig in Axe is not standard to the trig you learned in school. There are no degrees or radians. There are only sine and cosine functions (of which all normal functions can be derived from). The period of these functions is 256, and the amplitude 128 (signed).
To get a sine of an angle (0-255, not 0-359), it is simply sin(angle)//127 (make sure it is // and not /, due to the output being signed). The same works with cosine.

Since my super hexagon engine is done in polar coordinates, it is easier with this case, but there is only one more step with using

Now: here's some code before I explain how to do stuff (copied from graph-link):

.HEXAGON

ExprOn

For(A,0,7)
0ü{A+L}
End

64ü{1+L}

128ü{3+L}

192ü{5+L}

0ü{7+L}

0üXüAüBüCüD
1üF
2üE
65435üW
43üO
0üR

0üGüHüIüJüKüLüMüN

Repeat (getKey(15))
D+EüD
8*(getKey(3)-getKey(2))üC
X+CüX
If (Xùú8)
248üX
ElseIf (Xù255)
0üX
End
If (Dùú2)
254üD
F++
sub(A)
ElseIf (Dù255)
0üD
F++
sub(A)
End
10*cos(X+D)üA
10*sin(X+D)üB
ClrDraw
Pxl-On(47+(A//128),31+(B//128))
Line((7*cos(0*O+D))//128+47,(7*sin(0*O+D))//128+31,(7*cos(1*O+D))//128+47,(7*sin(1*O+D))//128+31)
Line((7*cos(1*O+D))//128+47,(7*sin(1*O+D))//128+31,(7*cos(2*O+D))//128+47,(7*sin(2*O+D))//128+31)
Line((7*cos(2*O+D))//128+47,(7*sin(2*O+D))//128+31,(7*cos(3*O+D))//128+47,(7*sin(3*O+D))//128+31)
Line((7*cos(3*O+D))//128+47,(7*sin(3*O+D))//128+31,(7*cos(4*O+D))//128+47,(7*sin(4*O+D))//128+31)
Line((7*cos(4*O+D))//128+47,(7*sin(4*O+D))//128+31,(7*cos(5*O+D))//128+47,(7*sin(5*O+D))//128+31)
Line((7*cos(5*O+D))//128+47,(7*sin(5*O+D))//128+31,(7*cos(0*O+D))//128+47,(7*sin(0*O+D))//128+31)
sub(B)
DispGraph
End
Return

Lbl A
!If (F^5)
úEüE
End
Return

Lbl B
0üGüHüIüJüKüLüMüNüR
For(K,0,3)
{(2*K)+L}üH
{(2*K)+1+L}-6ü{(2*K)+1+L}
{(2*K)+1+L}/2üG
If (G÷7)
0ü{(2*K)+1+L}
{(2*K)+1+L}/2üG
End
For(L,0,5)
(G*cos(L*O+D))//128+47üI
(G*sin(L*O+D))//128+31üJ
(G*cos((L+1)*O+D))//128+47üM
(G*sin((L+1)*O+D))//128+31üN
If ((J<<0) and (N<<0))
ElseIf (J<<0)
J*sin(O-(448-(L*O+D)))//127//sin(64-(O-(448-(L*O+D))))//127+IüI
0üJ
ElseIf (N<<0)
N*sin(O-(448-((L+1)*O+D)))//127//sin(64-(O-(448-((L+1)*O+D))))//127+MüM
0üN
End
If ((J>>63) and (N>>63))
ElseIf (J>>63)
J*sin(O-(448-(L*O+D)))//127//sin(64-(O-(448-(L*O+D))))//127+IüI
63üJ
ElseIf (N>>63)
N*sin(O-(448-((L+1)*O+D)))//127//sin(64-(O-(448-((L+1)*O+D))))//127+MüM
63üN
End
!If (H=L)
Line(I,J,M,N)
End
End
End
Return

We are only concerned with this segment of code:

Lbl B
0üGüHüIüJüKüLüMüNüR
For(K,0,3)
{(2*K)+L}üH
{(2*K)+1+L}-6ü{(2*K)+1+L}
{(2*K)+1+L}/2üG
If (G÷7)
0ü{(2*K)+1+L}
{(2*K)+1+L}/2üG
End
For(L,0,5)
(G*cos(L*O+D))//128+47üI
(G*sin(L*O+D))//128+31üJ
(G*cos((L+1)*O+D))//128+47üM
(G*sin((L+1)*O+D))//128+31üN
If ((J<<0) and (N<<0))
ElseIf (J<<0)
J*sin(O-(448-(L*O+D)))//127//sin(64-(O-(448-(L*O+D))))//127+IüI
0üJ
ElseIf (N<<0)
N*sin(O-(448-((L+1)*O+D)))//127//sin(64-(O-(448-((L+1)*O+D))))//127+MüM
0üN
End
If ((J>>63) and (N>>63))
ElseIf (J>>63)
J*sin(O-(448-(L*O+D)))//127//sin(64-(O-(448-(L*O+D))))//127+IüI
63üJ
ElseIf (N>>63)
N*sin(O-(448-((L+1)*O+D)))//127//sin(64-(O-(448-((L+1)*O+D))))//127+MüM
63üN
End
!If (H=L)
Line(I,J,M,N)
End
End
End
Return

Simply put: This is the display routine for incoming sprites. If it sees a line that is clipped, it fixes it.

This is the first little bit of code:

(G*cos(L*O+D))//128+47üI
(G*sin(L*O+D))//128+31üJ
(G*cos((L+1)*O+D))//128+47üM
(G*sin((L+1)*O+D))//128+31üN

It does the polar to rectangular conversion.

G is the radius, L*O is the angle of one point relative to D (which rotates everything, so it is added here), and (L+1)*O is the other

The 47 and 31 are the coordinates for the center of the screen (the origin)

If ((J<<0) and (N<<0))
ElseIf (J<<0)
J*sin(O-(448-(L*O+D)))//127//sin(64-(O-(448-(L*O+D))))//127+IüI
0üJ
ElseIf (N<<0)
N*sin(O-(448-((L+1)*O+D)))//127//sin(64-(O-(448-((L+1)*O+D))))//127+MüM
0üN
End
If ((J>>63) and (N>>63))
ElseIf (J>>63)
J*sin(O-(448-(L*O+D)))//127//sin(64-(O-(448-(L*O+D))))//127+IüI
63üJ
ElseIf (N>>63)
N*sin(O-(448-((L+1)*O+D)))//127//sin(64-(O-(448-((L+1)*O+D))))//127+MüM
63üN
End

This is the meat of the routine. It checks if an endpoint is out of bounds (and it both are, it does nothing) (Note: This routine was written for the top and bottom of the screen to be checked, but not the sides. It follows pretty much the same process, only the coordinates are flipped and 448 is 364)

The key is the law of sines: There is a triangle formed by the top border of the screen, the vertical line of the x coordinate of the point off-screen, and the line that is being clipped. By using this (the formula above) we can calculate the x coordinate of the point on the line that is at y=0

That is all. Remember to find your angles first if you are using rectangular coordinates. If you don't feel that I explained it well enough, please let me know and tell me what I need to explain.

With all these fancy contests around (with prizes and such), I thought it would be nice to see a contest. Just a contest. Nothing but a contest. No prizes. Just for the heck of it.

The rules are simple:

Make an Axe program that will amaze (you must not have been working on it before now). It can be math, games, whatever. Just do whatever inspires you.
Tell me what it will be on this thread. I will add you to the list of contestants.
Program it. You may not release source or binaries until the due date (screenies okay, though).
Have fun!  Your job is to make others like your project.
You may use axioms, but you may not create your own specifically for this task.
You may use external ASM code, but you may not create your own specifically for this task.

Due date: 12:00 AM on May 27, 2013

How to win: Community votes. I'll put a poll up and have a topic with all the files attached. The person with the most votes by June 1st wins!

Known Competitors:

Matrefeytontias

Ki1o

Does anybody know how to do this?

I am trying to make a program that will convert some stuffs to an Axe program, but I don't know how to create .8xp programs in Java.

Hayleia recently posted this: http://ourl.ca/17145

It got me thinking: how do I make a "more precise" method for greyscale and I came up with a semi-solution (no interrupts necessary!)



This is a calibration screen. At the end it prints the number to put in A, which is a semi-timer variable.

When I say semi, that means that the ability to do this has completely to do with the time the program takes to run (A is about 12 on my calc, but about 150 or 75 is needed for wabbit in my case.)

This works with 3 and 4 level grayscale, as shown with my screenie.

Without further ado: my code!

.AA

12->A
0->C
0->B

[FFFFFFFFFFFFFFFF]->Pic1

ClrDraw(rr)
For(X,0,11)
For(Y,0,7)
Pt-On(X*8,Y*8,Pic1)(r)
End
End

Repeat (getKey(54))
If (getKey)
Pause 250
End
getKey(4)-getKey(1)->B
A+B->A
If (A=0)
255->A
End
If (A=256)
1->A
End
C++
If (C->A)
DispGraph(r)
0->C
End
End
DispGraphClrDraw(rr)
ClrHome
Output(0,0,A>Dec)
Repeat (getKey(15))
End

The "sweet spot" A depends on the calculator and how quickly the program loops in its normal state, as well as how often you need to refresh the screen.

Possible use: pic viewers

Maybe possible use: non-action games (like chess)

Not possible use: action games

I hope this is helpful!

Hey, are there any good/easy to use Java game engines out there other than JMonkey out there?

I don't want to use JMonkey because it requires jdk 6, and I have jdk 7, and I don't want to downgrade...