Search found 35 matches

by Samson
Fri Jul 17, 2009 7:48 am
Forum: Gamecube/Wii Development
Topic: GX: a few technical questions
Replies: 3
Views: 3859

Re: GX: a few technical questions

tom34 wrote:- Using 2 TEV stages on a polygon seems to take as much fillrate as drawing that polygon twice. Is it normal? Is it the same with any number of TEV stages?
Do both the TEV stages require a texture fetch? And is the vertex cost low? Then I assume it must be nearly the same.
by Samson
Sun Jul 12, 2009 10:23 am
Forum: Gamecube/Wii Development
Topic: hw lighting
Replies: 4
Views: 4161

Re: hw lighting

Just be aware that each active light adds to the transform cost for each vertex! That's the same in DirectX and OpenGL or when you do your lighting in a vertex shader. In a professional game, even on next gen platforms like Xbox 360 or PS3, you try to have as few active lights as possible. If the li...
by Samson
Sat Jul 11, 2009 6:59 pm
Forum: Gamecube/Wii Development
Topic: Setting and Getting individual pixel colours
Replies: 1
Views: 2650

Re: Setting and Getting individual pixel colours

In general: you don't want to do that. If you want to draw sprites or glyphs for text it is much more efficient to store them as texture and draw screen-aligned quads. If you want to draw the result of some software rendering process it may still be more efficient to render into a texture and draw a...
by Samson
Wed Jun 03, 2009 12:31 am
Forum: devkitPPC
Topic: Launch a DOL or ELF file from another DOL or ELF file
Replies: 3
Views: 3496

Re: Launch a DOL or ELF file from another DOL or ELF file

I wrote a bit of code like that a while ago on GameCube. The problem is that a DOL file is not relocatable, and that the GC doesn't do any memory remapping (under normal circumstances). So you've got three choices: when making the second DOL make sure the memory regions don't overlap with the first ...
by Samson
Sun Jan 25, 2009 9:40 pm
Forum: Gamecube/Wii Development
Topic: SYS_GetFontTexture & SYS_GetFontTexel
Replies: 12
Views: 9634

Re: SYS_GetFontTexture & SYS_GetFontTexel

Maybe because xpos is not reset to 0 for each row? I assume ypos is initialised to 0.
by Samson
Sun Dec 07, 2008 5:22 pm
Forum: Suggestions and Feedback
Topic: new function in libogc GX
Replies: 2
Views: 3145

Re: new function in libogc GX

The GX functions are a very thin wrapper around the GameCube 3D hardware. So you'll have to look through the hardware documentation to see if you can do something before it can be added to the GX library.
by Samson
Tue Nov 18, 2008 11:50 pm
Forum: Gamecube/Wii Development
Topic: Vertex formats...
Replies: 3
Views: 3603

Re: Vertex formats...

The reason I was asking is, the VtxDesc contains which elements of a vertex are present, and if they're direct, or if they use an 8 or 16 bit index. So if you've got different shaders it would be something you're changing very frequently. On the other hand I can see myself settling for only a handfu...
by Samson
Tue Nov 11, 2008 8:27 pm
Forum: Gamecube/Wii Development
Topic: Crash on u32 binary comparison
Replies: 3
Views: 3047

Re: Crash on u32 binary comparison

Interesting. Is it possible that not the test itself is the problem, but that the extra code moves some data or other stuff to trigger a crash? Does it crash on that instruction? Did you have a look at the assembler output, if the compiler does anything weird? Did you try without optimisations?
by Samson
Sun Nov 09, 2008 9:12 pm
Forum: Gamecube/Wii Development
Topic: SYS_GetFontTexture & SYS_GetFontTexel
Replies: 12
Views: 9634

Re: SYS_GetFontTexture & SYS_GetFontTexel

Based on yagcd the font is a compressed I4 texture. And looking at libogc/system.c I'd say SYS_InitFont decompresses the font and fills in the font header with the information how to render text. SYS_GetFontTexture seems to just return the texture address and glyph position, if you want to render it...
by Samson
Sun Nov 09, 2008 8:58 pm
Forum: Gamecube/Wii Development
Topic: Vertex formats...
Replies: 3
Views: 3603

Vertex formats...

I'm a bit confused by vertex formats and vertex descriptions in libogc, for example: GX_ClearVtxDesc(); GX_SetVtxDesc(GX_VA_POS, GX_DIRECT); GX_SetVtxDesc(GX_VA_NBT, GX_DIRECT); GX_SetVtxDesc(GX_VA_TEX0, GX_DIRECT); GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_POS, GX_POS_XYZ, GX_F32, 0); GX_SetVtxAttrFmt(GX_...