Graphics/3D/nehe/lesson10b/source/nehe10b.cpp

/****************************************
 *      NDS NeHe Lesson 10b             *
 *      Author: Dovoto                  *
 ****************************************/

// include your libnds
#include <nds.h>

#include <malloc.h>
#include <stdio.h>

#include "Mud_pcx.h"
#include "World_txt.h"


int DrawGLScene();

int heading;
int32 xpos;
int32 zpos;

int yrot;               // Y Rotation
int32 walkbias = 0;
int walkbiasangle = 0;
int lookupdown = 0;


int texture[1];         // Storage For 1 Textures (only going to use 1 on the DS for this demo)

typedef struct tagVERTEX {
    v16 x, y, z;
    t16 u, v;
} VERTEX;

typedef struct tagTRIANGLE {
    VERTEX vertex[3];
} TRIANGLE;

typedef struct tagSECTOR {
    int numtriangles;
    TRIANGLE* triangle;
} SECTOR;

SECTOR sector1;             // Our Model Goes Here:

u8* file = (u8*)World_txt;

void myGetStr(char* buff, int size) {

    *buff = *file++;

    while( (*buff != '\n') && (*buff != 0xD)) {
        buff++;
        *buff = *file++;
    }
    
    buff[0] = '\n'; 
    buff[1] = 0;
    
}


void readstr(char *string) {

    do {
        myGetStr(string, 255);
    } while ((string[0] == '/') || (string[0] == '\n' ));

}

void SetupWorld() {
    float x, y, z; 
    float u, v;
    int numtriangles;
    char oneline[255];

    readstr(oneline);
    sscanf(oneline, "NUMPOLLIES %d\n", &numtriangles);

    sector1.triangle = (TRIANGLE*)malloc(numtriangles*sizeof(TRIANGLE));
    sector1.numtriangles = numtriangles;
    
    for (int loop = 0; loop < numtriangles; loop++) {
        for (int vert = 0; vert < 3; vert++) {
            readstr(oneline);
            sscanf(oneline, "%f %f %f %f %f", &x, &y, &z, &u, &v);
            sector1.triangle[loop].vertex[vert].x = floattov16(x);
            sector1.triangle[loop].vertex[vert].y = floattov16(y);
            sector1.triangle[loop].vertex[vert].z = floattov16(z);
            sector1.triangle[loop].vertex[vert].u = floattot16(u*128);
            sector1.triangle[loop].vertex[vert].v = floattot16(v*128);
        }
    }
    
    return;
}
int LoadGLTextures() {          // Load PCX files And Convert To Textures
    sImage pcx;                 //(NEW) and different from nehe.

    //load our texture
    loadPCX((u8*)Mud_pcx, &pcx);
    
    image8to16(&pcx);

    glGenTextures(1, &texture[0]);
    glBindTexture(0, texture[0]);
    glTexImage2D(0, 0, GL_RGB, TEXTURE_SIZE_128 , TEXTURE_SIZE_128, 0, TEXGEN_TEXCOORD | GL_TEXTURE_WRAP_S | GL_TEXTURE_WRAP_T, pcx.image.data8);

    return TRUE;
}

int main() {    
    
    // Setup the Main screen for 3D 
    videoSetMode(MODE_0_3D);
    vramSetBankA(VRAM_A_TEXTURE);                        //NEW  must set up some memory for textures
    
    // initialize the geometry engine
    glInit();
    
    // enable textures
    glEnable(GL_TEXTURE_2D);
    
    // enable antialiasing
    glEnable(GL_ANTIALIAS);
    
    // setup the rear plane
    glClearColor(0,0,0,31); // BG must be opaque for AA to work
    glClearPolyID(63); // BG must have a unique polygon ID for AA to work
    glClearDepth(0x7FFF);
    
    // Set our viewport to be the same size as the screen
    glViewport(0,0,255,191);
    
    LoadGLTextures();
    SetupWorld();
    
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(70, 256.0 / 192.0, 0.1, 100);
    
    glColor3f(1,1,1);
    
    glLight(0, RGB15(31,31,31) , 0, floattov10(-1.0), 0);
    
    //need to set up some material properties since DS does not have them set by default
    glMaterialf(GL_AMBIENT, RGB15(16,16,16));
    glMaterialf(GL_DIFFUSE, RGB15(16,16,16));
    glMaterialf(GL_SPECULAR, BIT(15) | RGB15(8,8,8));
    glMaterialf(GL_EMISSION, RGB15(16,16,16));
    
    //ds uses a table for shinyness..this generates a half-ass one
    glMaterialShinyness();
    
    //ds specific, several attributes can be set here   
    glPolyFmt(POLY_ALPHA(31) | POLY_CULL_NONE | POLY_FORMAT_LIGHT0);
    
    // Set the current matrix to be the model matrix
    glMatrixMode(GL_MODELVIEW);
    
    while (1) {
        //these little button functions are pretty handy
        scanKeys();
                
        int held = keysHeld();
        
        if (held & KEY_A) {
            lookupdown -= 1;
        }

        if (held & KEY_B) {
            lookupdown += 1;
        }
        
        if (held & KEY_LEFT) {
            heading += 64;  
            yrot = heading;
        }

        if (held & KEY_RIGHT) {
            heading -= 64;
            yrot = heading;
        }

        if (held & KEY_DOWN) {
            
            xpos += sinLerp(heading)/20;
            zpos += cosLerp(heading)/20;

            walkbiasangle+= 640;
            
            walkbias = sinLerp(walkbiasangle)/20;
        }

        if (held & KEY_UP) {
            xpos -= sinLerp(heading)/20;
            zpos -= cosLerp(heading)/20;

            walkbiasangle-= 640;
            
            walkbias = sinLerp(walkbiasangle)/20;
        }
        
        DrawGLScene();
        
        // flush to screen  
        glFlush(0);
        
        // wait for the screen to refresh
        swiWaitForVBlank();
    }
    
    return 0;
}

int DrawGLScene() {                         // Here's Where We Do All The Drawing

    // Reset The View

    v16 x_m, y_m, z_m;
    t16 u_m, v_m;
    s32 xtrans = -xpos;
    s32 ztrans = -zpos;
    s32 ytrans = -walkbias-(1<<10);
    int sceneroty = LUT_SIZE - yrot;
    
    glLoadIdentity();
    
    int numtriangles;

    glRotatef32i(lookupdown,(1<<12),0,0);
    glRotatef32i(sceneroty,0,(1<<12),0);
    
    glTranslatef32(xtrans, ytrans, ztrans);
    glBindTexture(GL_TEXTURE_2D, texture[0]);
    
    numtriangles = sector1.numtriangles;
    
    
    // Process Each Triangle
    for (int loop_m = 0; loop_m < numtriangles; loop_m++) {

        glBegin(GL_TRIANGLES);
            glNormal(NORMAL_PACK( 0, 0, 1<<10));
            x_m = sector1.triangle[loop_m].vertex[0].x;
            y_m = sector1.triangle[loop_m].vertex[0].y;
            z_m = sector1.triangle[loop_m].vertex[0].z;
            u_m = sector1.triangle[loop_m].vertex[0].u;
            v_m = sector1.triangle[loop_m].vertex[0].v;
            glTexCoord2t16(u_m,v_m); glVertex3v16(x_m,y_m,z_m);
            
            x_m = sector1.triangle[loop_m].vertex[1].x;
            y_m = sector1.triangle[loop_m].vertex[1].y;
            z_m = sector1.triangle[loop_m].vertex[1].z;
            u_m = sector1.triangle[loop_m].vertex[1].u;
            v_m = sector1.triangle[loop_m].vertex[1].v;
            glTexCoord2t16(u_m,v_m); glVertex3v16(x_m,y_m,z_m);
            
            x_m = sector1.triangle[loop_m].vertex[2].x;
            y_m = sector1.triangle[loop_m].vertex[2].y;
            z_m = sector1.triangle[loop_m].vertex[2].z;
            u_m = sector1.triangle[loop_m].vertex[2].u;
            v_m = sector1.triangle[loop_m].vertex[2].v;
            glTexCoord2t16(u_m,v_m); glVertex3v16(x_m,y_m,z_m);
        glEnd();
    }
    return TRUE;                                        // Everything Went OK

}