input/Touch_Pad/touch_look/source/main.cpp

/********************************************************************************************
 *      Nehe lesson 10 modification which uses the touch screen to control the camera and dpad
 *      to move the player.

 *      Author: revo                                                                        *
 *      Updated by revo (from 10b) - added camera moving by touching touch screen
 *
 ********************************************************************************************/

#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[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' ));
}

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;
}

// Load PCX files And Convert To Textures
int LoadGLTextures() {
    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);

    imageDestroy(&pcx);

    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 3D engine
    glInit();
    
    // enable textures
    glEnable(GL_TEXTURE_2D);
    
    // Set our viewport to be the same size as the screen
    glViewport(0,0,255,191);
    
    // setup the projection matrix
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(70, 256.0 / 192.0, 0.1, 100);
    
    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);
    
    // Specify the Clear Color and Depth
    glClearColor(0,0,0,31);
    glClearDepth(0x7FFF);
    
    // set the vertex color to white
    glColor3f(1.0,1.0,1.0);
    
    LoadGLTextures();
    SetupWorld();

    touchPosition   thisXY;
    touchPosition   lastXY = { 0,0,0,0 };       

    while (1)
    {
        //these little button functions are pretty handy
        scanKeys();

        if (keysHeld() & (KEY_LEFT|KEY_Y))
        {
            xpos -= sinLerp(heading + degreesToAngle(90)) >> 5;
            zpos += cosLerp(heading + degreesToAngle(90)) >> 5;
        }
        if (keysHeld() & (KEY_RIGHT|KEY_A))
        {
            xpos += sinLerp(heading + degreesToAngle(90)) >> 5;
            zpos -= cosLerp(heading + degreesToAngle(90)) >> 5;
        }
        if (keysHeld() & (KEY_DOWN|KEY_B))
        {

            xpos -= sinLerp(heading)>>5;
            zpos += cosLerp(heading)>>5;

            walkbiasangle += degreesToAngle(5);

            walkbias = sinLerp(walkbiasangle)>>4;
        }
        if (keysHeld() & (KEY_UP|KEY_X))
        {
            xpos += sinLerp(heading) >> 5;
            zpos -= cosLerp(heading) >> 5;

            if (walkbiasangle <= 0)
            {
                walkbiasangle = DEGREES_IN_CIRCLE;
            }
            else
            {
                walkbiasangle -= degreesToAngle(5);
            }
            walkbias = sinLerp(walkbiasangle)>>4;
        }

        // Camera rotation by touch screen

        if (keysHeld() & KEY_TOUCH)
        {
            touchRead(&thisXY);

            int16 dx = thisXY.px - lastXY.px;
            int16 dy = thisXY.py - lastXY.py;

            // filtering measurement errors
            if (dx<20 && dx>-20 && dy<20 && dy>-20)
            {
                if(dx>-3&&dx<3)
                    dx=0;

                if(dy>-2&&dy<2)
                    dy=0;

                    lookupdown -= degreesToAngle(dy);

                    heading += degreesToAngle(dx);
                    yrot = heading;
            }

            lastXY = thisXY;
        }


        //Push our original Matrix onto the stack (save state)
        glPushMatrix();

        DrawGLScene();

        // Pop our Matrix from the stack (restore state)
        glPopMatrix(1);

        // flush to screen
        glFlush(0);

    }

    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 = DEGREES_IN_CIRCLE - 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

}