C/C++ Programming Help Thread

[b-k24]

can someone show me how to create a simple bullet system for a side scroller game

[eldiablov]

At least pretend you have tried to code one.

[yaustar]

When bullet is fired, create a new bullet object.
Give the new bullet object a start position and a velocity.
Add the bullet object to the list of bullets.
Every frame, iterate through the list, update the position of each bullet based on it's velocity and time elapsed since last frame. Also check with if the bullet has collided with another object.
If you want to destroy the bullet, remove it from the list.

[b-k24]

i eventually figured it out thanks anyway yaustar

[heri7491]

sort of off topic, but how long do you think it would take for a n00b to figure out how to do some basic things in lua? and what specific program is recommended?

[Khatharr]

Well, it depends on the noob. If you're posting Lua questions in the C/C++ help thread then probably a long time. If you want to learn Lua then the program you'll want to work with would probably be Lua. If you want to use Lua on the PSP then LuaPlayer.

[Insert_Witty_Name]

<shameless plug>Or PGE Lua</shameless plug>

[Mr305]

I was wondering How I can obtain FPS in VSH's context? :confusion:

I'm out of ideas... :o

[Access_Denied]

I was wondering How I can obtain FPS in VSH's context? :confusion:

I'm out of ideas... :o

Wouldn't it be like counting the FPS in any other program? Just count the number of loops your program does in a set period of time. You can use psprtc.h to get the system time.

[Mr305]

Wouldn't it be like counting the FPS in any other program? Just count the number of loops your program does in a set period of time. You can use psprtc.h to get the system time.

No, because our thread isnt as complicated as VSH's. FPS is as high as 1280 based on thread delay which IS wrong.

[b-k24]

ok i need alil help..i know alot of ppl in this qj forum dnt want to help noobs..anyway i know some will so asking asking what i am doing wrong in these lines of code,

// Here it is the begin of the player jump code



if (osl_keys->held.cross && sprite->y == 200)
{if (!collision(sprite,sprite->x, sprite->y - 2, platform, platform->x, platform->y ))// test collision - 2 pixel

sprite_vel_y = 20;
sprite_jumping = 1;
}
if (!collision(sprite, sprite->x, sprite->y + 2, platform, platform->x, platform->y ))// test collision + 2 pixel


if (sprite_jumping == 1) /* Move sprite if we are jumping */
{
sprite_vel_y = sprite_vel_y - sprite_accel;
sprite->y = sprite->y - sprite_vel_y;

}

if (sprite->y >= 200) /* Check to see if sprite has hit floor */
{
sprite_vel_y = 0;
sprite_jumping = 0;
sprite->y = 200;
}

ok here is my explaination of whats wrong, i try to make my sprite jump on to a small platform.i did the collision function thing if am correct and i got to the point where the sprite gets collision block when its under the platform and tries to jump which is a good thing and when i jump on to it i get collision and the sprite just stays there cnt be moved, i cnt seem to make my sprite jump off again i think i know whats the problem but being a noob 2days trying to slove it on my own just isnt helping lol plz point me int the right direction.tanx

[slicer4ever]

cleaned up code a bit

if (osl_keys->held.cross && sprite->y == 200){
   if (!collision(sprite,sprite->x, sprite->y - 2, platform, platform->x, platform->y)){
      sprite_vel_y = 20;
   }
   sprite_jumping = 1;
}

if (!collision(sprite, sprite->x, sprite->y + 2, platform, platform->x, platform->y )){
   if (sprite_jumping == 1){
      sprite_vel_y = sprite_vel_y - sprite_accel;
      sprite->y = sprite->y - sprite_vel_y;
   }
}

if (sprite->y >= 200){
   sprite_vel_y = 0;
   sprite_jumping = 0; //never reset if on tile(at least not with the code shown here)
   sprite->y = 200;
}

now than, i can't see the problem with just this code, at the same time i put {}'s around all the if statements,

anyways, can you show the movement code also.

and finally, just to clarify the problem, once on a tile, you can not move any longer
anyways, if you could show us your movement code, and when collision is detected on a tile code, that'd help.

[b-k24]

This is the movement code..its a side scoller game..

if (osl_keys->held.left)
{
if (!collision(sprite, sprite->x -2, sprite->y, platform, platform->x, platform->y ))// test collision - 2 pixel
{
sprite->x -= 1;
}
}

if (osl_keys->held.right)
{
if (!collision(sprite, sprite->x +2, sprite->y, platform, platform->x, platform->y )) // test collision + 2 pixel
{
sprite->x += 1;
}

}

[slicer4ever]

well their we go=-)

if (osl_keys->held.left){
   if (!collision(sprite, sprite->x -2, sprite->y, platform, platform->x, platform->y )){
      sprite->x -= 1;
   }//think about this if statement...if it's not colliding than move, however if it is....i think you can see where i'm going with this
}

if (osl_keys->held.right){
   if (!collision(sprite, sprite->x +2, sprite->y, platform, platform->x, platform->y )){
      sprite->x += 1;
   }//same here
}

hope this helps, i suggest removing:
if (!collision(sprite, sprite->x +2, sprite->y, platform, platform->x, platform->y )){
if your doing this so if you horizontal checking for a collision, i'd suggest changing it so that the collision function returns a number indicating rather it's a vertical collision or a horizontal collision, hope this helps

[b-k24]

ok ill give it a try

[basfreak]

What do i use to blit a string in vsh (4.01)

[Davee]

What do i use to blit a string in vsh (4.01)

Vshblitter.

[PirataNervo]

Search at psp-programming.com for VSH Blitter 0.2

[basfreak]

Ok got it.

But i got an error:

$ make
psp-gcc -I/usr/local/pspdev/psp/sdk/include/libc -I. -I/usr/local/pspdev/psp/
/include -O2 -G0 -Wall -D_PSP_FW_VERSION=401   -c -o blit.o blit.c
blit.c: In function 'blit_setup':
blit.c:51: warning: passing argument 4 of 'sceDisplayGetFrameBuf' makes integ
from pointer without a cast
blit.c: In function 'blit_string46':
blit.c:141: warning: passing argument 4 of 'sceDisplayGetFrameBuf' makes inte
 from pointer without a cast
blit.c: In function 'FillRect':
blit.c:263: warning: assignment from incompatible pointer type
blit.c:260: warning: unused variable 'vptr0'
blit.c: In function 'FillRect2':
blit.c:283: warning: assignment from incompatible pointer type
blit.c: In function 'Fillvram':
blit.c:300: warning: assignment from incompatible pointer type
blit.c: In function 'FillvramPlus':
blit.c:315: warning: assignment from incompatible pointer type
psp-gcc -I/usr/local/pspdev/psp/sdk/include/libc -I. -I/usr/local/pspdev/psp/
/include -O2 -G0 -Wall -D_PSP_FW_VERSION=401   -c -o graphics.o graphics.c
graphics.c:8:21: error: jpeglib.h: No such file or directory
graphics.c:9:20: error: jerror.h: No such file or directory
graphics.c:152: warning: 'struct jpeg_decompress_struct' declared inside para
er list
graphics.c:152: warning: its scope is only this definition or declaration, wh
 is probably not what you want
graphics.c:152: error: parameter 1 ('dinfo') has incomplete type
graphics.c: In function 'loadJpegImageImpl':
graphics.c:154: warning: implicit declaration of function 'jpeg_read_header'
graphics.c:157: warning: implicit declaration of function 'jpeg_start_decompr
'
graphics.c:160: warning: implicit declaration of function 'jpeg_destroy_decom
ss'
graphics.c:177: error: 'JCS_GRAYSCALE' undeclared (first use in this function
graphics.c:177: error: (Each undeclared identifier is reported only once
graphics.c:177: error: for each function it appears in.)
graphics.c:180: warning: implicit declaration of function 'jpeg_read_scanline
graphics.c:201: warning: implicit declaration of function 'jpeg_finish_decomp
s'
graphics.c: In function 'loadJpegImage':
graphics.c:209: error: storage size of 'dinfo' isn't known
graphics.c:210: error: storage size of 'jerr' isn't known
graphics.c:211: warning: implicit declaration of function 'jpeg_std_error'
graphics.c:212: warning: implicit declaration of function 'jpeg_create_decomp
s'
graphics.c:218: warning: implicit declaration of function 'jpeg_stdio_src'
graphics.c:219: error: type of formal parameter 1 is incomplete
graphics.c:210: warning: unused variable 'jerr'
graphics.c:209: warning: unused variable 'dinfo'
graphics.c: At top level:
graphics.c:227: error: field 'pub' has incomplete type
graphics.c:232: error: expected specifier-qualifier-list before 'JOCTET'
graphics.c:241: warning: return type defaults to 'int'
graphics.c: In function 'METHODDEF':
graphics.c:241: error: expected declaration specifiers before 'mem_init_sourc
graphics.c:255: error: expected declaration specifiers before 'METHODDEF'
graphics.c:289: error: expected declaration specifiers before 'METHODDEF'
graphics.c:305: error: expected declaration specifiers before 'METHODDEF'
graphics.c:309: error: expected declaration specifiers before 'GLOBAL'
graphics.c:338: error: storage class specified for parameter 'PngData'
graphics.c:341: error: expected '=', ',', ';', 'asm' or '__attribute__' befor
{' token
graphics.c:353: error: expected '=', ',', ';', 'asm' or '__attribute__' befor
{' token
graphics.c:386: error: expected '=', ',', ';', 'asm' or '__attribute__' befor
{' token
graphics.c:392: error: expected '=', ',', ';', 'asm' or '__attribute__' befor
{' token
graphics.c:497: error: expected '=', ',', ';', 'asm' or '__attribute__' befor
{' token
graphics.c:526: error: old-style parameter declarations in prototyped functio
efinition
graphics.c:526: error: expected '{' at end of input
make: *** [graphics.o] Error 1

[Davee]

You're compiling graphics.c under kernel libs?

[PirataNervo]

You must install jpeg lib. Get it from SVN

[basfreak]

Hmm,

$ make
psp-gcc -I/usr/local/pspdev/psp/sdk/include/libc -I. -I/usr/local/pspdev/psp/sdk
/include -O2 -G0 -Wall -D_PSP_FW_VERSION=401  -L. -L/usr/local/pspdev/psp/sdk/li
b -specs=/usr/local/pspdev/psp/sdk/lib/prxspecs -Wl,-q,-T/usr/local/pspdev/psp/s
dk/lib/linkfile.prx -mno-crt0 -nostartfiles  main.o blit.o graphics.o /usr/local
/pspdev/psp/sdk/lib/prxexports.o -lpspsdk -lpspctrl -lpsppower -lpsprtc -lpspdeb
ug -lpspdisplay -lpspge -lpspctrl -lpspsdk -lpsplibc -lpspnet -lpspnet_inet -lps
pnet_apctl -lpspnet_resolver -lpsputility -lpspuser -lpspkernel -o LastTime.elf
graphics.o: In function `jpeg_mem_src':
graphics.c:(.text+0x118): undefined reference to `jpeg_resync_to_restart'
graphics.c:(.text+0x120): undefined reference to `jpeg_resync_to_restart'
graphics.o: In function `ReadPngData':
graphics.c:(.text+0x2ac): undefined reference to `png_get_io_ptr'
graphics.o: In function `loadJpegImageImpl':
graphics.c:(.text+0x5ac): undefined reference to `jpeg_read_header'
graphics.c:(.text+0x5bc): undefined reference to `jpeg_start_decompress'
graphics.c:(.text+0x5ec): undefined reference to `jpeg_destroy_decompress'
graphics.c:(.text+0x690): undefined reference to `jpeg_read_scanlines'
graphics.c:(.text+0x6b4): undefined reference to `jpeg_finish_decompress'
graphics.c:(.text+0x6bc): undefined reference to `jpeg_destroy_decompress'
graphics.c:(.text+0x6f4): undefined reference to `jpeg_read_scanlines'
graphics.o: In function `loadJpegImage':
graphics.c:(.text+0x7ec): undefined reference to `jpeg_std_error'
graphics.c:(.text+0x800): undefined reference to `jpeg_CreateDecompress'
graphics.c:(.text+0x82c): undefined reference to `jpeg_stdio_src'
graphics.c:(.text+0x864): undefined reference to `jpeg_destroy_decompress'
graphics.o: In function `loadPngImageImpl':
graphics.c:(.text+0x888): undefined reference to `png_create_info_struct'
graphics.c:(.text+0x89c): undefined reference to `png_set_sig_bytes'
graphics.c:(.text+0x8a8): undefined reference to `png_read_info'
graphics.c:(.text+0x8d0): undefined reference to `png_get_IHDR'
graphics.c:(.text+0x8fc): undefined reference to `png_destroy_read_struct'
graphics.c:(.text+0x978): undefined reference to `png_set_strip_16'
graphics.c:(.text+0x980): undefined reference to `png_set_packing'
graphics.c:(.text+0x9a8): undefined reference to `png_get_valid'
graphics.c:(.text+0x9c0): undefined reference to `png_set_filler'
graphics.c:(.text+0xa14): undefined reference to `png_read_row'
graphics.c:(.text+0xa84): undefined reference to `png_read_end'
graphics.c:(.text+0xa94): undefined reference to `png_destroy_read_struct'
graphics.c:(.text+0xac4): undefined reference to `png_set_gray_1_2_4_to_8'
graphics.c:(.text+0xad4): undefined reference to `png_set_tRNS_to_alpha'
graphics.c:(.text+0xae4): undefined reference to `png_set_palette_to_rgb'
graphics.c:(.text+0xb08): undefined reference to `png_destroy_read_struct'
graphics.c:(.text+0xb54): undefined reference to `png_destroy_read_struct'
graphics.c:(.text+0xb9c): undefined reference to `png_destroy_read_struct'
graphics.o: In function `loadImageFromMemory':
graphics.c:(.text+0xc04): undefined reference to `jpeg_std_error'
graphics.c:(.text+0xc18): undefined reference to `jpeg_CreateDecompress'
graphics.c:(.text+0xcb4): undefined reference to `png_create_read_struct'
graphics.c:(.text+0xcdc): undefined reference to `png_set_read_fn'
graphics.o: In function `loadPngImage':
graphics.c:(.text+0xd70): undefined reference to `png_create_read_struct'
graphics.c:(.text+0xd88): undefined reference to `png_init_io'
collect2: ld returned 1 exit status
make: *** [LastTime.elf] Error 1

[Insert_Witty_Name]

You also need to link -ljpeg -lpng -lz.

Good luck getting that plugin to load with all that bloat :)

[Mr305]

I was wondering How I can obtain FPS in VSH's context? :confusion:

I'm out of ideas... :o

Quoting...

[basfreak]

Ok im really confused right now

$ make
psp-gcc -I/usr/local/pspdev/psp/sdk/include/libc -I. -I/usr/local/pspdev/psp/sdk
/include -O2 -G0 -Wall -D_PSP_FW_VERSION=401  -L. -L/usr/local/pspdev/psp/sdk/li
b -specs=/usr/local/pspdev/psp/sdk/lib/prxspecs -Wl,-q,-T/usr/local/pspdev/psp/s
dk/lib/linkfile.prx -mno-crt0 -nostartfiles  main.o blit.o graphics.o /usr/local
/pspdev/psp/sdk/lib/prxexports.o -lpspsdk -lpspctrl -lpsppower -lpsprtc -ljpeg -
lpng -lz -lpspdebug -lpspdisplay -lpspge -lpspctrl -lpspsdk -lpsplibc -lpspnet -
lpspnet_inet -lpspnet_apctl -lpspnet_resolver -lpsputility -lpspuser -lpspkernel
 -o LastTime.elf
/usr/local/pspdev/lib/gcc/psp/4.1.0/../../../../psp/lib/libjpeg.a(jerror.o): In
function `output_message':
jerror.c:(.text+0x224): undefined reference to `_impure_ptr'
jerror.c:(.text+0x224): relocation truncated to fit: R_MIPS_GPREL16 against `_im
pure_ptr'
/usr/local/pspdev/lib/gcc/psp/4.1.0/../../../../psp/lib/libjpeg.a(jmemmgr.o): In
 function `jinit_memory_mgr':
jmemmgr.c:(.text+0x77c): undefined reference to `sscanf'
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngerror.o): In function `png_warning':
pngerror.c:(.text+0x14c): undefined reference to `_impure_ptr'
pngerror.c:(.text+0x14c): relocation truncated to fit: R_MIPS_GPREL16 against `_
impure_ptr'
pngerror.c:(.text+0x1a8): undefined reference to `_impure_ptr'
pngerror.c:(.text+0x1a8): relocation truncated to fit: R_MIPS_GPREL16 against `_
impure_ptr'
pngerror.c:(.text+0x1ac): undefined reference to `_impure_ptr'
pngerror.c:(.text+0x1ac): relocation truncated to fit: R_MIPS_GPREL16 against `_
impure_ptr'
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngerror.o): In function `png_error':
pngerror.c:(.text+0x2a8): undefined reference to `_impure_ptr'
pngerror.c:(.text+0x2a8): relocation truncated to fit: R_MIPS_GPREL16 against `_
impure_ptr'
pngerror.c:(.text+0x310): undefined reference to `_impure_ptr'
pngerror.c:(.text+0x310): relocation truncated to fit: R_MIPS_GPREL16 against `_
impure_ptr'
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngerror.o):pngerror.c:(.text+0x314): mor
e undefined references to `_impure_ptr' follow
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngerror.o): In function `png_error':
pngerror.c:(.text+0x314): relocation truncated to fit: R_MIPS_GPREL16 against `_
impure_ptr'
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngrtran.o): In function `png_build_gamma
_table':
pngrtran.c:(.text+0x1228): undefined reference to `pow'
pngrtran.c:(.text+0x1418): undefined reference to `pow'
pngrtran.c:(.text+0x14bc): undefined reference to `pow'
pngrtran.c:(.text+0x15c0): undefined reference to `pow'
pngrtran.c:(.text+0x1694): undefined reference to `pow'
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngrtran.o):pngrtran.c:(.text+0x1770): mo
re undefined references to `pow' follow
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngrutil.o): In function `png_handle_gAMA
':
pngrutil.c:(.text+0xd08): undefined reference to `_impure_ptr'
pngrutil.c:(.text+0xd08): relocation truncated to fit: R_MIPS_GPREL16 against `_
impure_ptr'
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngrutil.o): In function `png_handle_cHRM
$
pngrutil.c:(.text+0x146c): undefined reference to `_impure_ptr'
pngrutil.c:(.text+0x146c): relocation truncated to fit: R_MIPS_GPREL16 against `
_impure_ptr'
pngrutil.c:(.text+0x14dc): undefined reference to `_impure_ptr'
pngrutil.c:(.text+0x14dc): relocation truncated to fit: R_MIPS_GPREL16 against `
_impure_ptr'
/usr/local/pspdev/psp/sdk/lib/libpng.a(pngrutil.o): In function `png_handle_sRGB
':
pngrutil.c:(.text+0x178c): undefined reference to `_impure_ptr'
pngrutil.c:(.text+0x178c): additional relocation overflows omitted from the outp
ut
collect2: ld returned 1 exit status
make: *** [LastTime.elf] Error 1

[Insert_Witty_Name]

Don't link -lpsplibc.

Link -lm after -lz.
-=Double Post Merge =-

Quoting...

sceDisplayGetVcount() Maybe?

I'm guessing...

Or you could hook sceGuSwapBuffers() then time it as a regular FPS counter.

[basfreak]

$ make
psp-gcc -I. -I/usr/local/pspdev/psp/sdk/include -O2 -G0 -Wall -D_PSP_FW_VERSION=
401  -L. -L/usr/local/pspdev/psp/sdk/lib -specs=/usr/local/pspdev/psp/sdk/lib/pr
xspecs -Wl,-q,-T/usr/local/pspdev/psp/sdk/lib/linkfile.prx -mno-crt0 -nostartfil
es  main.o blit.o graphics.o /usr/local/pspdev/psp/sdk/lib/prxexports.o -lpspsdk
 -lpspctrl -lpsppower -lpsprtc -ljpeg -lpng -lz -lm -lpspdebug -lpspdisplay -lps
pge -lpspctrl -lpspsdk -lc -lpspnet -lpspnet_inet -lpspnet_apctl -lpspnet_resolv
er -lpsputility -lpspuser -lpspkernel -o LastTime.elf
graphics.o: In function `loadPngImageImpl':
graphics.c:(.text+0x904): undefined reference to `__iob'
graphics.c:(.text+0x910): undefined reference to `__iob'
graphics.c:(.text+0xb10): undefined reference to `__iob'
graphics.c:(.text+0xb1c): undefined reference to `__iob'
graphics.c:(.text+0xb5c): undefined reference to `__iob'
graphics.o:graphics.c:(.text+0xb68): more undefined references to `__iob' follow

collect2: ld returned 1 exit status
make: *** [LastTime.elf] Error 1

[PirataNervo]

make clean
make

[basfreak]

Hmmm, its build right now but still with errors:

$ make
psp-gcc -I. -I/usr/local/pspdev/psp/sdk/include -O2 -G0 -Wall -D_PSP_FW_V
401   -c -o main.o main.c
main.c: In function 'main_thread':
main.c:23: warning: unused variable 'pad'
main.c: At top level:
blit.h:13: warning: 'vram32' defined but not used
psp-gcc -I. -I/usr/local/pspdev/psp/sdk/include -O2 -G0 -Wall -D_PSP_FW_V
401   -c -o blit.o blit.c
blit.c: In function 'blit_setup':
blit.c:51: warning: passing argument 4 of 'sceDisplayGetFrameBuf' makes i
from pointer without a cast
blit.c: In function 'blit_string46':
blit.c:141: warning: passing argument 4 of 'sceDisplayGetFrameBuf' makes
 from pointer without a cast
blit.c: In function 'FillRect':
blit.c:263: warning: assignment from incompatible pointer type
blit.c:260: warning: unused variable 'vptr0'
blit.c: In function 'FillRect2':
blit.c:283: warning: assignment from incompatible pointer type
blit.c: In function 'Fillvram':
blit.c:300: warning: assignment from incompatible pointer type
blit.c: In function 'FillvramPlus':
blit.c:315: warning: assignment from incompatible pointer type
psp-gcc -I. -I/usr/local/pspdev/psp/sdk/include -O2 -G0 -Wall -D_PSP_FW_V
401   -c -o graphics.o graphics.c
graphics.c: In function 'blitImageToVram':
graphics.c:506: warning: assignment from incompatible pointer type
graphics.c: At top level:
blit.h:13: warning: 'vram32' defined but not used
psp-gcc -I. -I/usr/local/pspdev/psp/sdk/include -O2 -G0 -Wall -D_PSP_FW_V
401  -L. -L/usr/local/pspdev/psp/sdk/lib -specs=/usr/local/pspdev/psp/sdk
xspecs -Wl,-q,-T/usr/local/pspdev/psp/sdk/lib/linkfile.prx -mno-crt0 -nos
es  main.o blit.o graphics.o /usr/local/pspdev/psp/sdk/lib/prxexports.o -
 -lpspctrl -lpsppower -lpsprtc -ljpeg -lpng -lz -lm -lpspdebug -lpspdispl
pge -lpspctrl -lpspsdk -lc -lpspnet -lpspnet_inet -lpspnet_apctl -lpspnet
er -lpsputility -lpspuser -lpspkernel -o LastTime.elf
psp-fixup-imports LastTime.elf
psp-prxgen LastTime.elf LastTime.prx

[email protected] /cygdrive/c/psp/lasttime
$

[PirataNervo]

where are the errors?