As promised, some speed comparisons between Computer One Forth and SuperForth :
I will use the PERSPECTIVE.FTH program adding only a word to replace the infinite loop of AROUND by a DO loop. This word is called BROUND (why not ?). And I will also add a simpler word for DREAM called BREAM.
Code: Select all
: BREAM ( --- k ) 1 KEYROW
STEP POINT-OF-VIEW NIGHTMARE @ EXECUTE CLS ;
: BROUND ( n --- d )
TIME ROT ' NIGHTMARE !
64 = IF I . LEAVE THEN
TIME SWAP D- D. ;
The word BROUND will need to input the number n of desired loops and will return the difference in seconds d between two calls of TIME. I simplified BROUND compared to AROUND, it will not check for rotation changes, only watch the space bar, that may interrupt the looping ; in this case, you will also get the actual number of loops. Use BROUND for instance like this :
6000 6000 4000 POINT-OF-VIEW RZ 1000 BROUND AIRPLANE
The results are :
With SuperForth : 2400 secs
With Computer One Forth : 840 secs
The work to be done by this program is of two kinds :
- computations of the perspective transforms (in both cases with exactly the same all-Forth code)
- drawing lines (with my assembler word ADRAW for Computer One Forth and with a all-Forth equivalent for SuperForth)
because drawing with SuperForth needs to convert the 2D integer coordinates to floats for the QL to use its QDOS/SuperBasic graphics.
This equivalent, also called ADRAW, has exactly the same stack trace as the assembler word for ComputerOne :
ADRAW ( color, X1 , Y1, X2 , Y2 --- color, X2 , Y2 ) for chaining drawn lines just adding one new pair of coordinates.
To have the program do all the perspective computations (exactly the same code with both Forth) without drawing, i just had to modify the word SEG :
: SEG DUP ABS PIXEL ROT 0> IF ADRAW ELSE 2SWAP 2DROP THEN ;
: SEG DUP ABS PIXEL ROT 0> IF 2DROP ELSE 2SWAP 2DROP THEN ;
Without ADRAW, the (astonishing) results are :
With SuperForth : 1280 secs
With Computer One Forth : 610 secs
So, the part of this program only written in Forth runs two times faster on Computer One Forth than on SuperForth.
By difference :
My assembler ADRAW uses 130 secs (from the 840)
while the equivalent ADRAW for SuperForth through QL graphics needs 1120 secs (from the 2400)
As a conclusion, on a BBQL ComputerOne Forth draws my AIRPLANE every 0.8 secs, whereas SupperForth digests it in 2.4 secs. With my other Tetroid card (that has Minerva - but stays in Paris while I am still confined in the Alps) I thus may be able to animate 3D on a BBQL on one screen while displaying the other one with a periodicity of less than 1 sec.
Bye POLKA - Today I am 72, happy birthday to me !