Incidentally, what were your search terms? I have this crazy theory that Google does different searches for different people in different countries; mine are almost always the wrong ones.
As it turned out, it was extremely simple. You just need to:
1) Tell GX you will set 2 or more texcoords to generate ( GX_SetNumTexGens(2); GX_SetTexCoordGen(GX_TEXCOORD1, GX_TG_MTX2x4, GX_TG_TEX1, GX_IDENTITY); );
3) Tell GX how will pixels from previous stages will blend with the following ones ( GX_SetTevOp(GX_TEVSTAGE1, GX_BLEND); );
4) Specify which stages get which textures ( GX_LoadTexObj(&tex1, GX_TEXMAP0); GX_LoadTexObj(&tex2, GX_TEXMAP1); );
5) Alter your vertex descriptors appropiately ( GX_SetVtxDesc(GX_VA_TEX1, GX_DIRECT); GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_TEX1, GX_TEX_ST, GX_F32, 0); );
6) And, of course, call the appropiate texcoord specification functions twice or more, even if they use the same values ( GX_TexCoord2f32(0.0f,1.0f); GX_TexCoord2f32(0.0f,1.0f); ).
Code: Select all
/*---------------------------------------------------------------------------------
multitexture
modification to nehe lesson 6 port to GX, showing multiple textures per polygon
original port: shagkur
modifications: Izhido
---------------------------------------------------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <malloc.h>
#include <math.h>
#include <gccore.h>
#include <wiiuse/wpad.h>
// The two textures to use in this lesson
#include "crate_tpl.h"
#include "crate.h"
#include "NeHe_tpl.h"
#include "NeHe.h"
#define DEFAULT_FIFO_SIZE (256*1024)
static GXRModeObj *rmode = NULL;
static void *frameBuffer[2] = { NULL, NULL};
int main(int argc,char **argv)
{
f32 yscale;
u32 xfbHeight;
u32 fb = 0;
f32 rquad = 0.0f;
u32 first_frame = 1;
GXTexObj textureNeHe;
GXTexObj texturecrate;
Mtx view; // view and perspective matrices
Mtx model, modelview;
Mtx44 perspective;
void *gpfifo = NULL;
GXColor background = {0, 0, 0, 0xff};
guVector cam = {0.0F, 0.0F, 0.0F},
up = {0.0F, 1.0F, 0.0F},
look = {0.0F, 0.0F, -1.0F};
TPLFile neheTPL;
TPLFile crateTPL;
VIDEO_Init();
WPAD_Init();
rmode = VIDEO_GetPreferredMode(NULL);
// allocate the fifo buffer
gpfifo = memalign(32,DEFAULT_FIFO_SIZE);
memset(gpfifo,0,DEFAULT_FIFO_SIZE);
// allocate 2 framebuffers for double buffering
frameBuffer[0] = SYS_AllocateFramebuffer(rmode);
frameBuffer[1] = SYS_AllocateFramebuffer(rmode);
// configure video
VIDEO_Configure(rmode);
VIDEO_SetNextFramebuffer(frameBuffer[fb]);
VIDEO_Flush();
VIDEO_WaitVSync();
if(rmode->viTVMode&VI_NON_INTERLACE) VIDEO_WaitVSync();
fb ^= 1;
// init the flipper
GX_Init(gpfifo,DEFAULT_FIFO_SIZE);
// clears the bg to color and clears the z buffer
GX_SetCopyClear(background, 0x00ffffff);
// other gx setup
GX_SetViewport(0,0,rmode->fbWidth,rmode->efbHeight,0,1);
yscale = GX_GetYScaleFactor(rmode->efbHeight,rmode->xfbHeight);
xfbHeight = GX_SetDispCopyYScale(yscale);
GX_SetScissor(0,0,rmode->fbWidth,rmode->efbHeight);
GX_SetDispCopySrc(0,0,rmode->fbWidth,rmode->efbHeight);
GX_SetDispCopyDst(rmode->fbWidth,xfbHeight);
GX_SetCopyFilter(rmode->aa,rmode->sample_pattern,GX_TRUE,rmode->vfilter);
GX_SetFieldMode(rmode->field_rendering,((rmode->viHeight==2*rmode->xfbHeight)?GX_ENABLE:GX_DISABLE));
if (rmode->aa)
GX_SetPixelFmt(GX_PF_RGB565_Z16, GX_ZC_LINEAR);
else
GX_SetPixelFmt(GX_PF_RGB8_Z24, GX_ZC_LINEAR);
GX_SetCullMode(GX_CULL_NONE);
GX_CopyDisp(frameBuffer[fb],GX_TRUE);
GX_SetDispCopyGamma(GX_GM_1_0);
// setup the vertex attribute table
// describes the data
// args: vat location 0-7, type of data, data format, size, scale
// so for ex. in the first call we are sending position data with
// 3 values X,Y,Z of size F32. scale sets the number of fractional
// bits for non float data.
// An additional descriptor is added for a second texture.
GX_ClearVtxDesc();
GX_SetVtxDesc(GX_VA_POS, GX_DIRECT);
GX_SetVtxDesc(GX_VA_CLR0, GX_DIRECT);
GX_SetVtxDesc(GX_VA_TEX0, GX_DIRECT);
GX_SetVtxDesc(GX_VA_TEX1, GX_DIRECT); // <-- Texcoords for the second TEV
// Though not really relevant, the items here were rearranged
// so they match the previous lines
GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_POS, GX_POS_XYZ, GX_F32, 0);
GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_CLR0, GX_CLR_RGBA, GX_RGB8, 0);
GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_TEX0, GX_TEX_ST, GX_F32, 0);
GX_SetVtxAttrFmt(GX_VTXFMT0, GX_VA_TEX1, GX_TEX_ST, GX_F32, 0);
// set number of rasterized color channels
GX_SetNumChans(1);
//set number of texture coordinates to generate (two, for multitexture)
GX_SetNumTexGens(2);
// setup texture coordinate generation
// args: texcoord slot 0-7, matrix type, source to generate texture coordinates from, matrix to use
// The setup gets duplicated for both textures
GX_SetTexCoordGen(GX_TEXCOORD0, GX_TG_MTX2x4, GX_TG_TEX0, GX_IDENTITY);
GX_SetTexCoordGen(GX_TEXCOORD1, GX_TG_MTX2x4, GX_TG_TEX1, GX_IDENTITY);
GX_InvVtxCache();
GX_InvalidateTexAll();
// Opening both textures from header files
TPL_OpenTPLFromMemory(&crateTPL, (void *)crate_tpl,crate_tpl_size);
TPL_GetTexture(&crateTPL,crate,&texturecrate);
TPL_OpenTPLFromMemory(&neheTPL, (void *)NeHe_tpl,NeHe_tpl_size);
TPL_GetTexture(&neheTPL,nehe,&textureNeHe);
// setup our camera at the origin
// looking down the -z axis with y up
guLookAt(view, &cam, &up, &look);
// setup our projection matrix
// this creates a perspective matrix with a view angle of 90,
// and aspect ratio based on the display resolution
f32 w = rmode->viWidth;
f32 h = rmode->viHeight;
guPerspective(perspective, 45, (f32)w/h, 0.1F, 300.0F);
GX_LoadProjectionMtx(perspective, GX_PERSPECTIVE);
guVector cubeAxis = {1,1,1};
while(1) {
WPAD_ScanPads();
if ( WPAD_ButtonsDown(0) & WPAD_BUTTON_HOME) exit(0);
// Sets the number of TEV stages, so as to indicate we're using 2 textures.
// These lines do not really belong in here, since they can be called
// outside this loop; this was made to be consistent with the original ported example:
GX_SetNumTevStages(2);
// The first texture is used as the base for the cube; that is,
// the cube is intended to be a "crate":
GX_SetTevOp(GX_TEVSTAGE0, GX_REPLACE); // <-- Overwrite anything existing at that location
GX_SetTevOrder(GX_TEVSTAGE0, GX_TEXCOORD0, GX_TEXMAP0, GX_COLOR0A0);
// The second texture is blended with the first, giving it the impression
// of being a "sticker" plastered over the crate:
GX_SetTevOp(GX_TEVSTAGE1, GX_BLEND); // <-- Blend with previous texture
GX_SetTevOrder(GX_TEVSTAGE1, GX_TEXCOORD1, GX_TEXMAP1, GX_COLOR0A0);
guMtxIdentity(model);
guMtxRotAxisDeg(model, &cubeAxis, rquad);
guMtxTransApply(model, model, 1.5f,0.0f,-7.0f);
guMtxConcat(view,model,modelview);
// load the modelview matrix into matrix memory
GX_LoadPosMtxImm(modelview, GX_PNMTX0);
GX_LoadTexObj(&texturecrate, GX_TEXMAP0);
GX_LoadTexObj(&textureNeHe, GX_TEXMAP1);
GX_Begin(GX_QUADS, GX_VTXFMT0, 24); // Draw a Cube
GX_Position3f32(-1.0f, 1.0f, -1.0f); // Top Left of the quad (top)
GX_Color3f32(0.0f,1.0f,0.0f); // Set The Color To Green
GX_TexCoord2f32(0.0f,0.0f);
GX_TexCoord2f32(0.0f,0.0f);
GX_Position3f32(-1.0f, 1.0f, 1.0f); // Top Right of the quad (top)
GX_Color3f32(0.0f,1.0f,0.0f); // Set The Color To Green
GX_TexCoord2f32(1.0f,0.0f);
GX_TexCoord2f32(1.0f,0.0f);
GX_Position3f32(-1.0f, -1.0f, 1.0f); // Bottom Right of the quad (top)
GX_Color3f32(0.0f,1.0f,0.0f); // Set The Color To Green
GX_TexCoord2f32(1.0f,1.0f);
GX_TexCoord2f32(1.0f,1.0f);
GX_Position3f32(- 1.0f, -1.0f, -1.0f); // Bottom Left of the quad (top)
GX_Color3f32(0.0f,1.0f,0.0f); // Set The Color To Green
GX_TexCoord2f32(0.0f,1.0f);
GX_TexCoord2f32(0.0f,1.0f);
GX_Position3f32( 1.0f,1.0f, -1.0f); // Top Left of the quad (bottom)
GX_Color3f32(1.0f,0.5f,0.0f); // Set The Color To Orange
GX_TexCoord2f32(0.0f,0.0f);
GX_TexCoord2f32(0.0f,0.0f);
GX_Position3f32(1.0f,-1.0f, -1.0f); // Top Right of the quad (bottom)
GX_Color3f32(1.0f,0.5f,0.0f); // Set The Color To Orange
GX_TexCoord2f32(1.0f,0.0f);
GX_TexCoord2f32(1.0f,0.0f);
GX_Position3f32(1.0f,-1.0f,1.0f); // Bottom Right of the quad (bottom)
GX_Color3f32(1.0f,0.5f,0.0f); // Set The Color To Orange
GX_TexCoord2f32(1.0f,1.0f);
GX_TexCoord2f32(1.0f,1.0f);
GX_Position3f32( 1.0f,1.0f,1.0f); // Bottom Left of the quad (bottom)
GX_Color3f32(1.0f,0.5f,0.0f); // Set The Color To Orange
GX_TexCoord2f32(0.0f,1.0f);
GX_TexCoord2f32(0.0f,1.0f);
GX_Position3f32( -1.0f, -1.0f, 1.0f); // Top Right Of The Quad (Front)
GX_Color3f32(1.0f,0.0f,0.0f); // Set The Color To Red
GX_TexCoord2f32(0.0f,0.0f);
GX_TexCoord2f32(0.0f,0.0f);
GX_Position3f32(1.0f, -1.0f, 1.0f); // Top Left Of The Quad (Front)
GX_Color3f32(1.0f,0.0f,0.0f); // Set The Color To Red
GX_TexCoord2f32(1.0f,0.0f);
GX_TexCoord2f32(1.0f,0.0f);
GX_Position3f32(1.0f,-1.0f, -1.0f); // Bottom Left Of The Quad (Front)
GX_Color3f32(1.0f,0.0f,0.0f); // Set The Color To Red
GX_TexCoord2f32(1.0f,1.0f);
GX_TexCoord2f32(1.0f,1.0f);
GX_Position3f32( -1.0f,-1.0f, -1.0f); // Bottom Right Of The Quad (Front)
GX_Color3f32(1.0f,0.0f,0.0f); // Set The Color To Red
GX_TexCoord2f32(0.0f,1.0f);
GX_TexCoord2f32(0.0f,1.0f);
GX_Position3f32( -1.0f,1.0f,1.0f); // Bottom Left Of The Quad (Back)
GX_Color3f32(1.0f,1.0f,0.0f); // Set The Color To Yellow
GX_TexCoord2f32(0.0f,0.0f);
GX_TexCoord2f32(0.0f,0.0f);
GX_Position3f32(-1.0f,1.0f,-1.0f); // Bottom Right Of The Quad (Back)
GX_Color3f32(1.0f,1.0f,0.0f); // Set The Color To Yellow
GX_TexCoord2f32(1.0f,0.0f);
GX_TexCoord2f32(1.0f,0.0f);
GX_Position3f32(1.0f, 1.0f,-1.0f); // Top Right Of The Quad (Back)
GX_Color3f32(1.0f,1.0f,0.0f); // Set The Color To Yellow
GX_TexCoord2f32(1.0f,1.0f);
GX_TexCoord2f32(1.0f,1.0f);
GX_Position3f32( 1.0f, 1.0f,1.0f); // Top Left Of The Quad (Back)
GX_Color3f32(1.0f,1.0f,0.0f); // Set The Color To Yellow
GX_TexCoord2f32(0.0f,1.0f);
GX_TexCoord2f32(0.0f,1.0f);
GX_Position3f32(1.0f, -1.0f, -1.0f); // Top Right Of The Quad (Left)
GX_Color3f32(0.0f,0.0f,1.0f); // Set The Color To Blue
GX_TexCoord2f32(0.0f,0.0f);
GX_TexCoord2f32(0.0f,0.0f);
GX_Position3f32(1.0f, 1.0f,-1.0f); // Top Left Of The Quad (Left)
GX_Color3f32(0.0f,0.0f,1.0f); // Set The Color To Blue
GX_TexCoord2f32(1.0f,0.0f);
GX_TexCoord2f32(1.0f,0.0f);
GX_Position3f32(-1.0f,1.0f,-1.0f); // Bottom Left Of The Quad (Left)
GX_Color3f32(0.0f,0.0f,1.0f); // Set The Color To Blue
GX_TexCoord2f32(1.0f,1.0f);
GX_TexCoord2f32(1.0f,1.0f);
GX_Position3f32(-1.0f,-1.0f, -1.0f); // Bottom Right Of The Quad (Left)
GX_Color3f32(0.0f,0.0f,1.0f); // Set The Color To Blue
GX_TexCoord2f32(0.0f,1.0f);
GX_TexCoord2f32(0.0f,1.0f);
GX_Position3f32( 1.0f, -1.0f,1.0f); // Top Right Of The Quad (Right)
GX_Color3f32(1.0f,0.0f,1.0f); // Set The Color To Violet
GX_TexCoord2f32(0.0f,0.0f);
GX_TexCoord2f32(0.0f,0.0f);
GX_Position3f32( -1.0f, -1.0f, 1.0f); // Top Left Of The Quad (Right)
GX_Color3f32(1.0f,0.0f,1.0f); // Set The Color To Violet
GX_TexCoord2f32(1.0f,0.0f);
GX_TexCoord2f32(1.0f,0.0f);
GX_Position3f32( -1.0f,1.0f, 1.0f); // Bottom Left Of The Quad (Right)
GX_Color3f32(1.0f,0.0f,1.0f); // Set The Color To Violet
GX_TexCoord2f32(1.0f,1.0f);
GX_TexCoord2f32(1.0f,1.0f);
GX_Position3f32( 1.0f,1.0f,1.0f); // Bottom Right Of The Quad (Right)
GX_Color3f32(1.0f,0.0f,1.0f); // Set The Color To Violet
GX_TexCoord2f32(0.0f,1.0f);
GX_TexCoord2f32(0.0f,1.0f);
GX_End(); // Done Drawing The Quad
GX_SetZMode(GX_TRUE, GX_LEQUAL, GX_TRUE);
GX_SetColorUpdate(GX_TRUE);
GX_CopyDisp(frameBuffer[fb],GX_TRUE);
GX_DrawDone();
VIDEO_SetNextFramebuffer(frameBuffer[fb]);
if(first_frame) {
first_frame = 0;
VIDEO_SetBlack(FALSE);
}
VIDEO_Flush();
VIDEO_WaitVSync();
fb ^= 1;
rquad -= 0.15f; // Decrease The Rotation Variable For The Quad ( NEW )
}
}
