/***************************************************************************************
* Everything below has been designed and created By Andrew Davey *
* They are all of the functions needed by the program to create a height map *
*****************************************************************************************///============================================================
// v-- Loads the height data from a file.
//-------------------------------------------------
void map_loadHeightData(BYTE mapArray[MAP_WIDTH][MAP_HEIGHT]){
unsigned int w =0, h=0, size = w*h;
FILE *bmp = NULL;
//read as binary
bmp = fopen ("terrain.bmp","rb");
//move to the width and height of the imag in the header
fseek(bmp, 18, SEEK_SET);
//set the width of the file to w
fread(&w,4,1,bmp);
//set the height of the file to h
fread(&h,4,1,bmp);
//set the size of the file
size = w*h;
//check to see if the file is right size
if(w != MAP_WIDTH || h != MAP_HEIGHT){
printf("file size incorrect, closing\n");
fclose(bmp);
exit(0);
}//if
//ignore the plane and stuff and skip to end of header
fseek(bmp,28,SEEK_SET);
//read in the pixel information
fread(heightMapArray, size, 1, bmp);
//create a border around the hieghtmap,
//set all values on the first and last row to be 0 and the first and last olumn to be zero.
for(n=0;n<(int)w;n++)
for(i=0;i<(int)h;i++)
if(n == 0||n == 1024||i == 0||i == 1024)
// heightMapArray[n][i] = 0;
/*
//print array, check to see if the information is loading properly
for(n=0;n<1024;n++){
for(i=0;i<1024;i+=3) {
printf("Values: %d\t%d\t%d\n",(int)heightMapArray[n][i], (int)heightMapArray[n][i+2], (int)heightMapArray[n][i+3]);
}
}
*/
//cloase the file
fclose(bmp);
}//map_loadHeightData(BYTE[][])
//--------------------------------------------------------
// ^-- Loads the height data from a raw file.
// v-- draw the height map
//--------------------------------------------------------
void map_drawMap (){
//set up some variables for rendering
int row, column, x,y,z, switchSide;
switchSide =1;
//drawing the height map in quads.
glBegin(GL_TRIANGLE_STRIP);
for(row=0; row<=MAP_WIDTH; row+=QUAD_SIZE ){
//checkto see if the oposite direction should get rendered.
if(switchSide){
for(column = MAP_HEIGHT; column >= 0; column -= QUAD_SIZE){
//==============================================================
x = row;
y = heightMapArray[row][column];
z = column;
map_setColour(heightMapArray[x][y]);
glVertex3i( ( x * X_Z_MAG ), ( y * Y_MAG ), (z * X_Z_MAG) );
//==============================================================
x = row + QUAD_SIZE;
y = heightMapArray[row + QUAD_SIZE][column];
z = column;
map_setColour(heightMapArray[x][y]);
glVertex3i( ( x * X_Z_MAG ), ( y * Y_MAG ), (z * X_Z_MAG) );
//==============================================================
}//for(column)
}else{//switchSide
for(column =0; column <= MAP_HEIGHT; column += QUAD_SIZE){
//==============================================================
x = row + QUAD_SIZE;
y = heightMapArray[row+QUAD_SIZE][column];
z = column;
map_setColour(heightMapArray[x][y]);
glVertex3i( ( x * X_Z_MAG ), ( y * Y_MAG ), (z * X_Z_MAG) );
//==============================================================
x = row;
y = heightMapArray[row][column + QUAD_SIZE];
z = column + QUAD_SIZE;
map_setColour(heightMapArray[x][y]);
glVertex3i( ( x * X_Z_MAG ), ( y * Y_MAG ), (z * X_Z_MAG) );
//==============================================================
}//for(column)
}//switchSides
//make render the other direction
switchSide = !switchSide;
}//for(row)
glEnd();
}//map_drawMap()
//--------------------------------------------------------
// ^-- draw the height map
// v-- Calculate a colour for the vertex passed in
//--------------------------------------------------------
void map_setColour(BYTE height){
unsigned char r,g,b;
r= 0;
g= 256 - height;
b= 0;
glColor3ub(r,g,b);
}//map_setColour(BYTE)
/****************************************************************************************
* Everything above has been designed and created By Andrew Davey *
* They are all of the functions needed by the program to create a height map *
*****************************************************************************************/
