C programming
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glTexCoord is for what?texture?
the actual normal should look like this:
but without normal i tilted a little
and with normal after implement glnormal3d()
big issues:right i have problems like files with X>1 cannot loads,rendered model don't look like the actual model,the normal calculate could be wrong,haven't implement half-edge data structure use array.
good thing is I have learned C++ with realloc and malloc and difference with the java,render model with lightning,troubleshooting using visual studio
i still need to implement:x,y,z axis,user interface with gluts,grid system with 10x10,aabb systems
but without normal i tilted a little
and with normal after implement glnormal3d()
big issues:right i have problems like files with X>1 cannot loads,rendered model don't look like the actual model,the normal calculate could be wrong,haven't implement half-edge data structure use array.
good thing is I have learned C++ with realloc and malloc and difference with the java,render model with lightning,troubleshooting using visual studio
i still need to implement:x,y,z axis,user interface with gluts,grid system with 10x10,aabb systems
Last edited:
davidktw
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the actual normal should look like this:
but without normal i tilted a little
and with normal after implement glnormal3d()
big issues:right i have problems like files with X>1 cannot loads,rendered model don't look like the actual model,the normal calculate could be wrong,haven't implement half-edge data structure use array.
good thing is I have learned C++ with realloc and malloc and difference with the java,render model with lightning,troubleshooting using visual studio
i still need to implement:x,y,z axis,user interface with gluts,grid system with 10x10,aabb systems
Look at your screenshots, I think you ought to really look at how you form your mesh. I think it is wrong from step 1. You can ignore shading and so forth for now. Look at the first post that I show you the horse without normals, even that shows the shape of the horse. Even if your normals are not there, at least the 2D silhouette should resemble the shape of your mesh.
I believe you will want to print out all your vertices, match against your input file, see if you are consuming your vertices data properly or not. If this portion is right, then print out the vertices values just before you call glVertex3d functions, see if the vertices values are indeed what you consume and stored.
These are the basic debugging steps to trace where exactly is the issue.
davidktw
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Yes, glTextCoord is for texture mapping, you don't have to consider using it for now. Get your mesh correct first.
Code:
void displayModel(void){
//enable openGL depth test
glEnable(GL_DEPTH_TEST);
// Just clean the screen
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
// setup the perspective projection
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(60, 1, .1, 100);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(0,0,5,0,0,0,0,1,0);
glPushMatrix();
//rotate and scale the object
glRotatef(x_angle,0,1,0);
glRotatef(y_angle,1,0,0);
glScalef(scale_size,scale_size,scale_size);
for(int i = 0;i < f_size - 1;i++){
face f = face_array[i];
glColor3f(1.0, 1.0, 1.0);
glBegin(GL_TRIANGLES);
//glNormal3d(vertex_array[f.v1].nx,vertex_array[f.v1].ny,vertex_array[f.v1].nz);
glVertex3d(vertex_array[f.v1].x,vertex_array[f.v1].y,vertex_array[f.v1].z);
//glNormal3d(vertex_array[f.v2].nx,vertex_array[f.v2].ny,vertex_array[f.v2].nz);
glVertex3d(vertex_array[f.v2].x,vertex_array[f.v2].y,vertex_array[f.v2].z);
//glNormal3d(vertex_array[f.v3].nx,vertex_array[f.v3].ny,vertex_array[f.v3].nz);
glVertex3d(vertex_array[f.v3].x,vertex_array[f.v3].y,vertex_array[f.v3].z);
glEnd();
}
glPopMatrix();
glutSwapBuffers();
}my displaymodel() looks find rights?
then i need to do many printf and scanf.
davidktw
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It has nothing to do with your displaymode codes. Those are just 3D operations to control the presentation of data into the screen. Before you even get to this step, how can you be VERY SURE that v.x is indeed the x coordinate of the vertex ? Can you be very sure that when you read a vertex x coordinate as 123.45, indeed this is the actual value passed to OpenGL ? Can you be very sure that when you pass the x, y, z coordinates to OpenGL, all the values are referring to the same vertex ? Read you consume the values from the file correctly and pass them correctly to the OpenGL as intended ?
So far when I look at your screenshots, I don't think you did the above steps properly. Please go and validate your program is correct up to the point before you pass them to OpenGL.
btw i tried all the stricmp,strstr,strchk,all even char ch,say ch[0],all doesn't work for me.
but i learnt that fgetc can get the first character of the string
davidktw
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Have you even read in from the file or not ?
You can try use fscanf(FILE *, "%s", str_array) to capture a non-whitespace string, then you can always use "str_array[0] == ..." to test for the first character.
davidktw
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How does accessing the first character not work for u? I think u need to be more informative
i use char c;
davidktw
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I still don't get where you problem is. Look at my sample below
Code:
$ gcc -o readchar readchar.c
$ ./readchar <(echo "ABCDEF")
FILENAME=/dev/fd/63
FIRST CHARACTER=A
$ ./readchar <(echo "123456")
FILENAME=/dev/fd/63
FIRST CHARACTER=1
$ cat readchar.c
#include <stdio.h>
int main(int argc, char **argv) {
char buf[100];
FILE *fp = fopen(argv[1], "r");
printf("FILENAME=%s\n", argv[1]);
fscanf(fp, "%s", buf);
printf("FIRST CHARACTER=%c\n", buf[0]);
return 0;
}struct HE_edge {
HE_vert* vert; // vertex at the end of the half-edge
HE_edge* pair; // oppositely oriented half-edge
HE_face* face; // the incident face
HE_edge* prev; // previous half-edge around the face
HE_edge* next; // next half-edge around the face
};
Error E2139 read.c 6: Declaration missing ;
Error E2139 read.c 7: Declaration missing ;
Error E2139 read.c 8: Declaration missing ;
Error E2238 read.c 9: Multiple declaration for 'HE_edge'
when I am using borland it says declaration missing.
updated:I have solved this just need to add struct before cross reference
Last edited:
Hi there,
when I was trying to using:
struct HE_edge
{
struct HE_vert* vert; // vertex at the end of the half-edge
struct HE_edge* pair; // oppositely oriented half-edge
struct HE_face* face; // the incident face
struct HE_edge* prev; // previous half-edge around the face
struct HE_edge* next; // next half-edge around the face
};
then this function:
void output_face_vertices (struct HE_face* f)
{
HE_edge* first_edge = f->edge ;
output(first_edge-> vert) ;
HE_edge* second_edge = first_edge->next ;
output (second_edge->vert) ;
HE_edge* third_edge = second_edge->next ;
output(third_edge->vert) ;
}
tried to compile,
it mentioned that undefined symbol in function,
even if I put struct HE_edge it doesn't work out,
when I use visual studio_ i don't have such
when I was trying to using:
struct HE_edge
{
struct HE_vert* vert; // vertex at the end of the half-edge
struct HE_edge* pair; // oppositely oriented half-edge
struct HE_face* face; // the incident face
struct HE_edge* prev; // previous half-edge around the face
struct HE_edge* next; // next half-edge around the face
};
then this function:
void output_face_vertices (struct HE_face* f)
{
HE_edge* first_edge = f->edge ;
output(first_edge-> vert) ;
HE_edge* second_edge = first_edge->next ;
output (second_edge->vert) ;
HE_edge* third_edge = second_edge->next ;
output(third_edge->vert) ;
}
tried to compile,
it mentioned that undefined symbol in function,
even if I put struct HE_edge it doesn't work out,
when I use visual studio_ i don't have such
Last edited:
I recalled on lab8 for data structure I wrote some code for graphs an adjaceny matrix in java.
along the line teacher says need adjacency matrix,
Code:
public class Graph {
private int graphSize = 0;
private int adjacencyMatrix[][];
public Graph(int size) {
//create an adjacency matrix based on the graph size
graphSize = size;
adjacencyMatrix = new int[size][size];
for (int i = 0; i < adjacencyMatrix.length; i++) {
for (int j = 0; j < adjacencyMatrix[0].length; j++) {
adjacencyMatrix[i][j] = 0;
}
}
}
public void printAdjacencyMatrix() {
if (!isEmpty()) {
for (int i = 0; i < adjacencyMatrix.length; i++) {
for (int j = 0; j < adjacencyMatrix[0].length; j++) {
System.out.print(adjacencyMatrix[i][j] + " ");
}
System.out.println();
}
}
}
/*
* insert the edges given the adjacency matrix.
* it will be arranged as of undirected graph order
*/
public void insertEdge(int nodeID, int edge) {
//take in nodeID and its correspodning edges
//iterate through the adjacencymatrix
//set adjacencymatrix based on undirect graph pending
if (!isEmpty()) {
adjacencyMatrix[nodeID][edge] = 1;
//since must be undirected so
//adjacency matrix finally cloned
adjacencyMatrix[edge][nodeID] = 1;
}
}
public boolean isEmpty() {
return graphSize == 0;
}
/*
* Print out the depth first search tree from vertex v
*/
public void printDepthFirstSearch(int v) {
if (!isEmpty()) {
boolean[] isVisited = new boolean[graphSize];
//given a verticies
dfs2(v, isVisited);
System.out.println();
}
}
private void dfs2(int v, boolean isVisited[]) {
//this area will be visited starting from the int v
//for each vertex v visited
//store the visited vertex into an array
//if not visited then print it out
if(!isVisited[v]){
System.out.print(v + " ");
}
isVisited[v] = true;
//iterate through the adjacency matrix
//each neighbour of v
int count = 0;
for (int neigh = 0; neigh < adjacencyMatrix[v].length; neigh++) {
if (adjacencyMatrix[v][neigh] == 1) {//if it exist
if (!isVisited[neigh]) { //if not visited for that particular neighbour
count ++;
dfs2(neigh, isVisited);
}
}
}
if(count == 0) System.out.println();
}
/*
*
* Print the depth first search given the verticies
* @param v as the starting point
*/
public void printBreathFirstSearch(int v) {
if (!isEmpty()) {
boolean[] isVisited = new boolean[graphSize];
//given a verticies
bfs2(v, isVisited);
System.out.println();
}
}
//the int need to be a node?
private void bfs2(int v, boolean isVisited[]) {
Queue1 queue = new Queue1();
queue.enqueue(v);
isVisited[v] = true;
if(!isVisited[v]){
System.out.print(v + " ");
}
while (!queue.isEmpty()) {
int vertex = Integer.parseInt(queue.dequeue().toString());
//given the vertex
for (int neigh = 0; neigh < adjacencyMatrix[vertex].length;neigh ++ ) {//for each neigh
if (adjacencyMatrix[vertex][neigh] == 1 && !isVisited[neigh]) {
//been visited
queue.enqueue(new Integer(neigh));//pending recursive visiting
//dequeue to search for more neighbours
bfs2(Integer.parseInt(queue.dequeue().toString()), isVisited);
}
//create a new line to break
}
}
}
public void printConnectedComponents() {
if (!isEmpty()) {
boolean[] isVisited = new boolean[graphSize];
for(int neigh = 0;neigh < adjacencyMatrix.length;neigh++){
//break
dfs2(neigh,isVisited);
}
System.out.println();
}
}
}I also wrote before some code for reading graphs from a text files:
Code:
/*
* Read the graph from a text file.
*/
public static void readFile() {
int nodeID, size, numOfEdge,edge, count = 0;
try {
System.out.println("Enter the file name:");
Scanner in = new Scanner(new File(console.nextLine()));
size = in.nextInt();//verticies size
g = new Graph(size);
//not useful in this case as can get size from the lab8
for (int j = 0; j < size; j++) {
//first ndode past through already
nodeID = in.nextInt();
count++;
//check the number of edges
numOfEdge = in.nextInt();
for (int k = 0; k < numOfEdge; k++) {
//insert the edge with regards to the node id
edge = in.nextInt();
g.insertEdge(nodeID, edge);
}
}
// if need for debugging just use this method
// g.printAdjacencyMatrix();
//send the vertices and its edges to the adjacency matrix
} catch (FileNotFoundException ex) {
System.out.println("File not found!");
}
System.out.println(count + " nodes read");
}the format is like that:
6
0 2 1 2
1 2 0 2
2 3 0 1 3
3 1 2
4 1 5
5 1 4
still trying to figure out between graphs and half-edge data structure,
btw my mesh is only need triangle only.no need for rect,poly,tetra etcs.
davidktw
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The full type of a structure is inclusive of the "struct" keyword.
You can define your own type and hence have the syntax more friendly looking as such
Code:
//assuming the following types are already created
// typedef struct _HE_face_ { ... } HE_face;
// typedef struct _HE_vert_ { ... } HE_vert;
typedef struct _HE_edge_
{
HE_vert* vert; // vertex at the end of the half-edge
struct _HE_edge_* pair; // oppositely oriented half-edge
HE_face* face; // the incident face
struct _HE_edge_* prev; // previous half-edge around the face
struct _HE_edge_* next; // next half-edge around the face
} HE_edge;Inside the structure declaration, "HE_edge" type is not fully declared yet, hence you still need to stick with "struct _HE_edge_" as the complete type since there is a reference inside the structure declaration.
After the new type "HE_edge" is declared, you can use it as such
Code:
void output_face_vertices (HE_face* f)
{
HE_edge* first_edge = f->edge ;
output(first_edge->vert) ;
HE_edge* second_edge = first_edge->next ;
output(second_edge->vert) ;
HE_edge* third_edge = second_edge->next ;
output(third_edge->vert) ;
}I was thinking whether to store them into array first,because need to cross references,then store them into half-edge
http://stackoverflow.com/questions/556095/loading-a-model-into-a-half-edge-data-structure-from-a-ply-file
perhaps this is related to the ply model?
it says something like using a mark method to ensure that it was already visited,i recalled I learnt before a mark method to check if it is visited.
the problem is how to cross-reference,
http://www.flipcode.com/
it will read the vertex first,
then read the face,
but face normal vertex to do calculation of normal,
in between need to store in the mesh data structure
after that vertex normal need faces.
http://stackoverflow.com/questions/556095/loading-a-model-into-a-half-edge-data-structure-from-a-ply-file
perhaps this is related to the ply model?
it says something like using a mark method to ensure that it was already visited,i recalled I learnt before a mark method to check if it is visited.
the problem is how to cross-reference,
http://www.flipcode.com/
it will read the vertex first,
then read the face,
but face normal vertex to do calculation of normal,
in between need to store in the mesh data structure
after that vertex normal need faces.
Last edited:
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