/* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above notice and this permission notice shall be included in all copies
* or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <fstream>
#include <vector>
#include "imageloader.h"
#include "md2model.h"
using namespace std;
namespace {
//Normals used in the MD2 file format
float NORMALS[486] =
{-0.525731f, 0.000000f, 0.850651f,
-0.442863f, 0.238856f, 0.864188f,
-0.295242f, 0.000000f, 0.955423f,
-0.309017f, 0.500000f, 0.809017f,
-0.162460f, 0.262866f, 0.951056f,
0.000000f, 0.000000f, 1.000000f,
0.000000f, 0.850651f, 0.525731f,
-0.147621f, 0.716567f, 0.681718f,
0.147621f, 0.716567f, 0.681718f,
0.000000f, 0.525731f, 0.850651f,
0.309017f, 0.500000f, 0.809017f,
0.525731f, 0.000000f, 0.850651f,
0.295242f, 0.000000f, 0.955423f,
0.442863f, 0.238856f, 0.864188f,
0.162460f, 0.262866f, 0.951056f,
-0.681718f, 0.147621f, 0.716567f,
-0.809017f, 0.309017f, 0.500000f,
-0.587785f, 0.425325f, 0.688191f,
-0.850651f, 0.525731f, 0.000000f,
-0.864188f, 0.442863f, 0.238856f,
-0.716567f, 0.681718f, 0.147621f,
-0.688191f, 0.587785f, 0.425325f,
-0.500000f, 0.809017f, 0.309017f,
-0.238856f, 0.864188f, 0.442863f,
-0.425325f, 0.688191f, 0.587785f,
-0.716567f, 0.681718f, -0.147621f,
-0.500000f, 0.809017f, -0.309017f,
-0.525731f, 0.850651f, 0.000000f,
0.000000f, 0.850651f, -0.525731f,
-0.238856f, 0.864188f, -0.442863f,
0.000000f, 0.955423f, -0.295242f,
-0.262866f, 0.951056f, -0.162460f,
0.000000f, 1.000000f, 0.000000f,
0.000000f, 0.955423f, 0.295242f,
-0.262866f, 0.951056f, 0.162460f,
0.238856f, 0.864188f, 0.442863f,
0.262866f, 0.951056f, 0.162460f,
0.500000f, 0.809017f, 0.309017f,
0.238856f, 0.864188f, -0.442863f,
0.262866f, 0.951056f, -0.162460f,
0.500000f, 0.809017f, -0.309017f,
0.850651f, 0.525731f, 0.000000f,
0.716567f, 0.681718f, 0.147621f,
0.716567f, 0.681718f, -0.147621f,
0.525731f, 0.850651f, 0.000000f,
0.425325f, 0.688191f, 0.587785f,
0.864188f, 0.442863f, 0.238856f,
0.688191f, 0.587785f, 0.425325f,
0.809017f, 0.309017f, 0.500000f,
0.681718f, 0.147621f, 0.716567f,
0.587785f, 0.425325f, 0.688191f,
0.955423f, 0.295242f, 0.000000f,
1.000000f, 0.000000f, 0.000000f,
0.951056f, 0.162460f, 0.262866f,
0.850651f, -0.525731f, 0.000000f,
0.955423f, -0.295242f, 0.000000f,
0.864188f, -0.442863f, 0.238856f,
0.951056f, -0.162460f, 0.262866f,
0.809017f, -0.309017f, 0.500000f,
0.681718f, -0.147621f, 0.716567f,
0.850651f, 0.000000f, 0.525731f,
0.864188f, 0.442863f, -0.238856f,
0.809017f, 0.309017f, -0.500000f,
0.951056f, 0.162460f, -0.262866f,
0.525731f, 0.000000f, -0.850651f,
0.681718f, 0.147621f, -0.716567f,
0.681718f, -0.147621f, -0.716567f,
0.850651f, 0.000000f, -0.525731f,
0.809017f, -0.309017f, -0.500000f,
0.864188f, -0.442863f, -0.238856f,
0.951056f, -0.162460f, -0.262866f,
0.147621f, 0.716567f, -0.681718f,
0.309017f, 0.500000f, -0.809017f,
0.425325f, 0.688191f, -0.587785f,
0.442863f, 0.238856f, -0.864188f,
0.587785f, 0.425325f, -0.688191f,
0.688191f, 0.587785f, -0.425325f,
-0.147621f, 0.716567f, -0.681718f,
-0.309017f, 0.500000f, -0.809017f,
0.000000f, 0.525731f, -0.850651f,
-0.525731f, 0.000000f, -0.850651f,
-0.442863f, 0.238856f, -0.864188f,
-0.295242f, 0.000000f, -0.955423f,
-0.162460f, 0.262866f, -0.951056f,
0.000000f, 0.000000f, -1.000000f,
0.295242f, 0.000000f, -0.955423f,
0.162460f, 0.262866f, -0.951056f,
-0.442863f, -0.238856f, -0.864188f,
-0.309017f, -0.500000f, -0.809017f,
-0.162460f, -0.262866f, -0.951056f,
0.000000f, -0.850651f, -0.525731f,
-0.147621f, -0.716567f, -0.681718f,
0.147621f, -0.716567f, -0.681718f,
0.000000f, -0.525731f, -0.850651f,
0.309017f, -0.500000f, -0.809017f,
0.442863f, -0.238856f, -0.864188f,
0.162460f, -0.262866f, -0.951056f,
0.238856f, -0.864188f, -0.442863f,
0.500000f, -0.809017f, -0.309017f,
0.425325f, -0.688191f, -0.587785f,
0.716567f, -0.681718f, -0.147621f,
0.688191f, -0.587785f, -0.425325f,
0.587785f, -0.425325f, -0.688191f,
0.000000f, -0.955423f, -0.295242f,
0.000000f, -1.000000f, 0.000000f,
0.262866f, -0.951056f, -0.162460f,
0.000000f, -0.850651f, 0.525731f,
0.000000f, -0.955423f, 0.295242f,
0.238856f, -0.864188f, 0.442863f,
0.262866f, -0.951056f, 0.162460f,
0.500000f, -0.809017f, 0.309017f,
0.716567f, -0.681718f, 0.147621f,
0.525731f, -0.850651f, 0.000000f,
-0.238856f, -0.864188f, -0.442863f,
-0.500000f, -0.809017f, -0.309017f,
-0.262866f, -0.951056f, -0.162460f,
-0.850651f, -0.525731f, 0.000000f,
-0.716567f, -0.681718f, -0.147621f,
-0.716567f, -0.681718f, 0.147621f,
-0.525731f, -0.850651f, 0.000000f,
-0.500000f, -0.809017f, 0.309017f,
-0.238856f, -0.864188f, 0.442863f,
-0.262866f, -0.951056f, 0.162460f,
-0.864188f, -0.442863f, 0.238856f,
-0.809017f, -0.309017f, 0.500000f,
-0.688191f, -0.587785f, 0.425325f,
-0.681718f, -0.147621f, 0.716567f,
-0.442863f, -0.238856f, 0.864188f,
-0.587785f, -0.425325f, 0.688191f,
-0.309017f, -0.500000f, 0.809017f,
-0.147621f, -0.716567f, 0.681718f,
-0.425325f, -0.688191f, 0.587785f,
-0.162460f, -0.262866f, 0.951056f,
0.442863f, -0.238856f, 0.864188f,
0.162460f, -0.262866f, 0.951056f,
0.309017f, -0.500000f, 0.809017f,
0.147621f, -0.716567f, 0.681718f,
0.000000f, -0.525731f, 0.850651f,
0.425325f, -0.688191f, 0.587785f,
0.587785f, -0.425325f, 0.688191f,
0.688191f, -0.587785f, 0.425325f,
-0.955423f, 0.295242f, 0.000000f,
-0.951056f, 0.162460f, 0.262866f,
-1.000000f, 0.000000f, 0.000000f,
-0.850651f, 0.000000f, 0.525731f,
-0.955423f, -0.295242f, 0.000000f,
-0.951056f, -0.162460f, 0.262866f,
-0.864188f, 0.442863f, -0.238856f,
-0.951056f, 0.162460f, -0.262866f,
-0.809017f, 0.309017f, -0.500000f,
-0.864188f, -0.442863f, -0.238856f,
-0.951056f, -0.162460f, -0.262866f,
-0.809017f, -0.309017f, -0.500000f,
-0.681718f, 0.147621f, -0.716567f,
-0.681718f, -0.147621f, -0.716567f,
-0.850651f, 0.000000f, -0.525731f,
-0.688191f, 0.587785f, -0.425325f,
-0.587785f, 0.425325f, -0.688191f,
-0.425325f, 0.688191f, -0.587785f,
-0.425325f, -0.688191f, -0.587785f,
-0.587785f, -0.425325f, -0.688191f,
-0.688191f, -0.587785f, -0.425325f};
//Returns whether the system is little-endian
bool littleEndian() {
//The short value 1 has bytes (1, 0) in little-endian and (0, 1) in
//big-endian
short s = 1;
return (((char*)&s)[0]) == 1;
}
//Converts a four-character array to an integer, using little-endian form
int toInt(const char* bytes) {
return (int)(((unsigned char)bytes[3] << 24) |
((unsigned char)bytes[2] << 16) |
((unsigned char)bytes[1] << 8) |
(unsigned char)bytes[0]);
}
//Converts a two-character array to a short, using little-endian form
short toShort(const char* bytes) {
return (short)(((unsigned char)bytes[1] << 8) |
(unsigned char)bytes[0]);
}
//Converts a two-character array to an unsigned short, using little-endian
//form
unsigned short toUShort(const char* bytes) {
return (unsigned short)(((unsigned char)bytes[1] << 8) |
(unsigned char)bytes[0]);
}
//Converts a four-character array to a float, using little-endian form
float toFloat(const char* bytes) {
float f;
if (littleEndian()) {
((char*)&f)[0] = bytes[0];
((char*)&f)[1] = bytes[1];
((char*)&f)[2] = bytes[2];
((char*)&f)[3] = bytes[3];
}
else {
((char*)&f)[0] = bytes[3];
((char*)&f)[1] = bytes[2];
((char*)&f)[2] = bytes[1];
((char*)&f)[3] = bytes[0];
}
return f;
}
//Reads the next four bytes as an integer, using little-endian form
int readInt(ifstream &input) {
char buffer[4];
input.read(buffer, 4);
return toInt(buffer);
}
//Reads the next two bytes as a short, using little-endian form
short readShort(ifstream &input) {
char buffer[2];
input.read(buffer, 2);
return toShort(buffer);
}
//Reads the next two bytes as an unsigned short, using little-endian form
unsigned short readUShort(ifstream &input) {
char buffer[2];
input.read(buffer, 2);
return toUShort(buffer);
}
//Reads the next four bytes as a float, using little-endian form
float readFloat(ifstream &input) {
char buffer[4];
input.read(buffer, 4);
return toFloat(buffer);
}
//Calls readFloat three times and returns the results as a Vec3f object
Vec3f readVec3f(ifstream &input) {
float x = readFloat(input);
float y = readFloat(input);
float z = readFloat(input);
return Vec3f(x, y, z);
}
//Makes the image into a texture, and returns the id of the texture
GLuint loadTexture(Image *image) {
GLuint textureId;
glGenTextures(1, &textureId);
glBindTexture(GL_TEXTURE_2D, textureId);
glTexImage2D(GL_TEXTURE_2D,
0,
GL_RGB,
image->width, image->height,
0,
GL_RGB,
GL_UNSIGNED_BYTE,
image->pixels);
return textureId;
}
}
MD2Model::~MD2Model() {
if (frames != NULL) {
for(int i = 0; i < numFrames; i++) {
delete[] frames[i].vertices;
}
delete[] frames;
}
if (texCoords != NULL) {
delete[] texCoords;
}
if (triangles != NULL) {
delete[] triangles;
}
}
MD2Model::MD2Model() {
frames = NULL;
texCoords = NULL;
triangles = NULL;
}
//Loads the MD2 model
MD2Model* MD2Model::load(const char* filename,
vector<const char*> textureFilenames) {
ifstream input;
input.open(filename, istream::binary);
char buffer[64];
input.read(buffer, 4); //Should be "IPD2", if this is an MD2 file
if (buffer[0] != 'I' || buffer[1] != 'D' ||
buffer[2] != 'P' || buffer[3] != '2') {
return NULL;
}
if (readInt(input) != 8) { //The version number
return NULL;
}
int textureWidth = readInt(input); //The width of the textures
int textureHeight = readInt(input); //The height of the textures
readInt(input); //The number of bytes per frame
int numTextures = readInt(input); //The number of textures
if (numTextures != 1) {
return NULL;
}
int numVertices = readInt(input); //The number of vertices
int numTexCoords = readInt(input); //The number of texture coordinates
int numTriangles = readInt(input); //The number of triangles
readInt(input); //The number of OpenGL commands
int numFrames = readInt(input); //The number of frames
//Offsets (number of bytes after the beginning of the file to the beginning
//of where certain data appear)
readInt(input); //The offset to the textures
int texCoordOffset = readInt(input); //The offset to the texture coordinates
int triangleOffset = readInt(input); //The offset to the triangles
int frameOffset = readInt(input); //The offset to the frames
readInt(input); //The offset to the OpenGL commands
readInt(input); //The offset to the end of the file
//Load the textures (ignore the texture suggested by the MD2 file)
MD2Model* model = new MD2Model();
for(unsigned int i = 0; i < textureFilenames.size(); i++) {
const char* f = textureFilenames[i];
if (strlen(f) < 5 ||
strcmp(f + strlen(f) - 4, ".bmp") != 0) {
delete model;
return NULL;
}
Image* image = loadBMP(f);
GLuint textureId = loadTexture(image);
delete image;
model->textureIds.push_back(textureId);
}
//Load the texture coordinates
input.seekg(texCoordOffset, ios_base::beg);
model->texCoords = new MD2TexCoord[numTexCoords];
for(int i = 0; i < numTexCoords; i++) {
MD2TexCoord* texCoord = model->texCoords + i;
texCoord->texCoordX = (float)readShort(input) / textureWidth;
texCoord->texCoordY = 1 - (float)readShort(input) / textureHeight;
}
//Load the triangles
input.seekg(triangleOffset, ios_base::beg);
model->triangles = new MD2Triangle[numTriangles];
model->numTriangles = numTriangles;
for(int i = 0; i < numTriangles; i++) {
MD2Triangle* triangle = model->triangles + i;
for(int j = 0; j < 3; j++) {
triangle->vertices[j] = readUShort(input);
}
for(int j = 0; j < 3; j++) {
triangle->texCoords[j] = readUShort(input);
}
}
//Load the frames
input.seekg(frameOffset, ios_base::beg);
model->frames = new MD2Frame[numFrames];
model->numFrames = numFrames;
for(int i = 0; i < numFrames; i++) {
MD2Frame* frame = model->frames + i;
frame->vertices = new MD2Vertex[numVertices];
Vec3f scale = readVec3f(input);
Vec3f translation = readVec3f(input);
input.read(frame->name, 16);
for(int j = 0; j < numVertices; j++) {
MD2Vertex* vertex = frame->vertices + j;
input.read(buffer, 3);
Vec3f v((unsigned char)buffer[0],
(unsigned char)buffer[1],
(unsigned char)buffer[2]);
vertex->pos = translation + Vec3f(scale[0] * v[0],
scale[1] * v[1],
scale[2] * v[2]);
input.read(buffer, 1);
int normalIndex = (int)((unsigned char)buffer[0]);
vertex->normal = Vec3f(NORMALS[3 * normalIndex],
NORMALS[3 * normalIndex + 1],
NORMALS[3 * normalIndex + 2]);
}
}
model->startFrame = 0;
model->endFrame = numFrames - 1;
return model;
}
void MD2Model::setAnimation(const char* name) {
/* The names of frames normally begin with the name of the animation in
* which they are, e.g. "run", and are followed by a non-alphabetical
* character. Normally, they indicate their frame number in the animation,
* e.g. "run_1", "run_2", etc.
*/
bool found = false;
for(int i = 0; i < numFrames; i++) {
MD2Frame* frame = frames + i;
if (strlen(frame->name) > strlen(name) &&
strncmp(frame->name, name, strlen(name)) == 0 &&
!isalpha(frame->name[strlen(name)])) {
if (!found) {
found = true;
startFrame = i;
}
else {
endFrame = i;
}
}
else if (found) {
break;
}
}
}
void MD2Model::draw(int textureNum, float time) {
if (time > -100000000 && time < 1000000000) {
time -= (int)time;
if (time < 0) {
time += 1;
}
}
else {
time = 0;
}
glEnable(GL_TEXTURE_2D);
//Use the appropriate texture
glBindTexture(GL_TEXTURE_2D, textureIds[textureNum]);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
//Figure out the two frames between which we are interpolating
int frameIndex1 = (int)(time * (endFrame - startFrame + 1)) + startFrame;
if (frameIndex1 > endFrame) {
frameIndex1 = startFrame;
}
int frameIndex2;
if (frameIndex1 < endFrame) {
frameIndex2 = frameIndex1 + 1;
}
else {
frameIndex2 = startFrame;
}
MD2Frame* frame1 = frames + frameIndex1;
MD2Frame* frame2 = frames + frameIndex2;
//Figure out the fraction that we are between the two frames
float frac =
(time - (float)(frameIndex1 - startFrame) /
(float)(endFrame - startFrame + 1)) * (endFrame - startFrame + 1);
//Draw the model as an interpolation between the two frames
glBegin(GL_TRIANGLES);
for(int i = 0; i < numTriangles; i++) {
MD2Triangle* triangle = triangles + i;
for(int j = 2; j >= 0; j--) {
MD2Vertex* v1 = frame1->vertices + triangle->vertices[j];
MD2Vertex* v2 = frame2->vertices + triangle->vertices[j];
Vec3f pos = v1->pos * (1 - frac) + v2->pos * frac;
Vec3f normal = v1->normal * (1 - frac) + v2->normal * frac;
if (normal[0] == 0 && normal[1] == 0 && normal[2] == 0) {
normal = Vec3f(0, 0, 1);
}
glNormal3f(normal[0], normal[1], normal[2]);
MD2TexCoord* texCoord = texCoords + triangle->texCoords[j];
glTexCoord2f(texCoord->texCoordX, texCoord->texCoordY);
glVertex3f(pos[0], pos[1], pos[2]);
}
}
glEnd();
}
