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

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

// include your ndslib
#include <nds.h>
#include <malloc.h>
#include <stdio.h>

//needed to load pcx files
#include <nds/arm9/image.h>
#include <nds/arm9/trig_lut.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[0];                     // 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' ));
        return;
}

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;                

        //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();
                                
        
                if (keysHeld() & KEY_A)
                {
                        lookupdown -= 1;
                }
                if (keysHeld() & KEY_B)
                {
                        lookupdown += 1;
                }
                
                if (keysHeld() & KEY_LEFT)
                {
                        heading += 64;  
                        yrot = heading;
                }
                if (keysHeld() & KEY_RIGHT)
                {
                        heading -= 64;
                        yrot = heading;
                }
                if (keysHeld() & KEY_DOWN)
                {
                        
                        xpos += sinLerp(heading)/20;
                        zpos += cosLerp(heading)/20;

                        walkbiasangle+= 640;
                        
                        walkbias = sinLerp(walkbiasangle)/20;
                }
                if (keysHeld() & 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;
        int32 xtrans = -xpos;
        int32 ztrans = -zpos;
        int32 ytrans = -walkbias-(1<<10);
        int sceneroty = LUT_SIZE - yrot;
        
        glLoadIdentity();
        
        int numtriangles;

        glRotatef32i(lookupdown,(1<<12),0,0);
        glRotatef32i(sceneroty,0,(1<<12),0);
        
        glTranslate3f32(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

}