...
Spock: Guessing is not in my nature, Doctor.
McCoy: Well... nobody's perfect.
A: Yes, though it depends what you mean by explain. I believe the Universe is everything and the only comprehensive explanation of the Universe is the Universe itself. However, explanation (the way I've learned that word) does not imply omniscience. Explanation is a model, an approximation of the whole, a valid generalization within certain (error) limits, something which attemps to converge towards the correct answer. Infinitely approach it, but never quite reach it. I believe we can make "the best guess" based on finite amount of information we've fed into the model, a guess we can be proud of, a guess which doesn't warrant regret even if we find points which won't fit. If that occurs, we'll just make a better guess, a more sophisticated guess, an educated guess.
http://en.wikipedia.org/wiki/Global_optimization
http://www.esrf.eu/computing/scientific/FIT2D/MF/node1.html
No matter how good you become, you'll never beat Moore's law, but even if you did, you'd still be stuck on this planet, in this solar system, this galaxy and this universe. How far is far enough?
--
Looking into building small executables (for anything) and possibly a small os and compiler for the raspberry pi...
; nasm -f bin elf_x86.asm
BITS 32
org 0x08048000
ehdr: ; Elf32_Ehdr
db 0x7F, "ELF", 1, 1, 1, 0 ; e_ident
times 8 db 0
dw 2 ; e_type
dw 3 ; e_machine
dd 1 ; e_version
dd _start ; e_entry
dd phdr - $$ ; e_phoff
dd 0 ; e_shoff
dd 0 ; e_flags
dw ehdrsize ; e_ehsize
dw phdrsize ; e_phentsize
dw 1 ; e_phnum
dw 0 ; e_shentsize
dw 0 ; e_shnum
dw 0 ; e_shstrndx
ehdrsize equ $ - ehdr
phdr: ; Elf32_Phdr
dd 1 ; p_type
dd 0 ; p_offset
dd $$ ; p_vaddr
dd $$ ; p_paddr
dd filesize ; p_filesz
dd filesize ; p_memsz
dd 5 ; p_flags
dd 0x1000 ; p_align
phdrsize equ $ - phdr
_start:
mov eax, 4 ; syscall 4: write
mov ebx, 1 ; stdout
mov ecx, msg ; message address
mov edx, 13 ; number of bytes
int 0x80 ; invoke syscall
mov eax, 1 ; syscall 1: exit
xor ebx, ebx ; return code 0
int 0x80 ; invoke syscall
msg: db 'hello, world',10,13 ; also \n
filesize equ $ - $$
decod@korpimaa:~/tiny$ nasm -f bin elf_x86.asm
decod@korpimaa:~/tiny$ ls -l elf_x86-rwxrwxr-x 1 decod decod 129 Nov 11 19:45 elf_x86
decod@korpimaa:~/tiny$ ./elf_x86
hello, world
/* x64 asm */
#define write(message, length) \
asm ( \
"mov $1, %%rax;" \
"mov $1, %%rdi;" \
"mov %0, %%rsi;" \
"mov %1, %%rdx;" \
"syscall" \
:: "r" (&message), "g" (length) \
: "rax", "rdi", "rsi", "rdx")
#define exit() \
asm ( \
"mov $60, %rax;" \
"mov $0, %rdi;" \
"syscall")
_start() {
char str[] = "Hello, World\n";
write(str, 13);
exit();
}
decod@korpimaa:~/tiny$ gcc -nostdlib hello_x86.c
decod@korpimaa:~/tiny$ strip a.out
decod@korpimaa:~/tiny$ ./a.out
Hello, World
decod@korpimaa:~/tiny$ ls -lah a.out
-rwxrwxr-x 1 decod decod 1.1K Nov 11 19:48 a.out
decod@korpimaa:~/tiny$ objcopy a.out -O binary
decod@korpimaa:~/tiny$ ls -lah a.out
-rwxrwxr-x 1 decod decod 192 Nov 11 19:49 a.out
------------------------------------------------------------------
"mov r0, $1;" \
"mov r1, %0;" \
"mov r2, $13;" \
"mov r7, $4;" \
"swi $0" \
:: "r" (msg) \
: "r0", "r1", "r2", "r7")
#define exit() asm ( \
"mov r0, $0;" \
"mov r7, $1;" \
"swi $0")
_start() {
char str[] = "Hello, World\n";
write(str);
exit();
}
pi@raspberrypi ~ $ gcc helloarm.c -nostdlib
pi@raspberrypi ~ $ strip a.out
pi@raspberrypi ~ $ ls -lah a.out
-rwxr-xr-x 1 pi pi 720 Nov 11 17:50 a.out
pi@raspberrypi ~ $ objcopy a.out -O binary
pi@raspberrypi ~ $ ls -lah a.out
-rwxr-xr-x 1 pi pi 140 Nov 11 17:50 a.out
------------------------------------------------------------------
ubuntu@ubuntu:~$ gcc -m32 otccelf.c
ubuntu@ubuntu:~$ ./a.out otccelf.c otccelf1
ubuntu@ubuntu:~$ chmod +x otccelf1
ubuntu@ubuntu:~$ ./otccelf1
usage: otccelf file.c outfile
ubuntu@ubuntu:~$ wget bellard.org/otcc/otccelfn.c
ubuntu@ubuntu:~$ wget bellard.org/otcc/otccex.c
ubuntu@ubuntu:~$ gcc -m32 otccelfn.c
ubuntu@ubuntu:~$ ./a.out otccex.c otccex
ubuntu@ubuntu:~$ chmod a+x otccex
ubuntu@ubuntu:~$ ./otccex
usage: ./otccex n [base]
Compute fib(n) and fact(n) and output the result in base 'base'
http://bellard.org/otcc/
Something to aim for...
------------------------------------------------------------------
http://www.cl.cam.ac.uk/projects/raspberrypi/tutorials/os/
------------------------------------------------------------------
Some old effects...
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <SDL/SDL.h>
int WinMain() {
SDL_Event event;
SDL_Surface *screen, *textureImg;
int quit = 0, shiftX, shiftY, shiftLookX, shiftLookY;
float timeDisplacement = 0.0;
int *p, *q;
int x, y;
int *distanceTable=(int *)malloc(4*1024*1024);
int *angleTable=(int *)malloc(4*1024*1024);
int w=512, h=512;
int angle;
int depth;
int texture_x=0, texture_y=0;
textureImg = SDL_LoadBMP("red_smoke.bmp");
for(x=0; x<w*2; x++)
for(y=0; y<h*2; y++) {
depth = 32.0 * 512 / sqrt(1.0*((x - w) * (x - w) + (y - h) * (y - h)));
angle = 0.5 * 512 * atan2(1.0*(y - h), 1.0*(x - w)) / 3.141592653589793;
distanceTable[x+y*1024] = depth;
angleTable[x+y*1024] = angle;
}
SDL_Init(SDL_INIT_VIDEO);
screen = SDL_SetVideoMode(512, 512, 32, SDL_HWSURFACE|SDL_DOUBLEBUF);
while(!quit) {
timeDisplacement += 0.015;
shiftX = 512 * .2 * timeDisplacement+300;
shiftY = 512 * .15 * timeDisplacement+300;
shiftLookX = w / 2 + 0*w / 4 * sin(timeDisplacement);
shiftLookY = h / 2 + 0*h / 4 * sin(timeDisplacement * 1.5);
for(y=0; y<512; y++)
for(x=0; x<512; x++) {
texture_x = abs((distanceTable[ (x+shiftLookX) + (y+shiftLookY)*1024] + shiftX)) % 512;
texture_y = abs((angleTable[ (x+shiftLookX) + (y+shiftLookY)*1024] + shiftY)) % 512;
q = (int *)textureImg->pixels+(texture_x+texture_y*511);
p = (int *)screen->pixels+(x+y*512);
*p = *q;
}
SDL_PollEvent(&event);
if(event.type==SDL_QUIT) quit = 1;
SDL_Flip(screen);
}
SDL_Quit();
free(distanceTable);
free(angleTable);
return 0;
}
--
You'd never let me win anyway...
...well, that wouldn't be winning.
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