I have been attempting to get an .obj file loaded into my OpenGl application and I thought it had finally done it, but on closer inspection the model appears to have been either turned into a super low poly version or the entire model has been flipped inside out resulting in the faces looking weirdly bumpy and the normals/textures yield unexpected results as well.
I am unsure whether this is caused by the loader or something else but to save posting a wall of text ill just post the loader code, if more code is needed let me know and I will update my question.
bool ObjLoader::loadOBJ(
const char * path,
std::vector<glm::vec3> & out_vertices,
std::vector<glm::vec2> & out_uvs,
std::vector<glm::vec3> & out_normals
)
{
printf("Loading OBJ file %s...\n", path);
std::vector<unsigned int> vertexIndices, uvIndices, normalIndices;
std::vector<glm::vec3> temp_vertices;
std::vector<glm::vec2> temp_uvs;
std::vector<glm::vec3> temp_normals;
FILE * file = fopen(path, "r");
if( file == NULL ){
printf("Cant find the file!!\n");
return false;
}
while( 1 ){
char lineHeader[128];
int res = fscanf(file, "%s", lineHeader);
if (res == EOF)
break;
if ( strcmp( lineHeader, "v" ) == 0 ){
glm::vec3 vertex;
fscanf(file, "%f %f %f\n", &vertex.x, &vertex.y, &vertex.z );
temp_vertices.push_back(vertex);
}else if ( strcmp( lineHeader, "vt" ) == 0 ){
glm::vec2 uv;
fscanf(file, "%f %f\n", &uv.x, &uv.y );
temp_uvs.push_back(uv);
}else if ( strcmp( lineHeader, "vn" ) == 0 ){
glm::vec3 normal;
fscanf(file, "%f %f %f\n", &normal.x, &normal.y, &normal.z );
temp_normals.push_back(normal);
}else if ( strcmp( lineHeader, "f" ) == 0 ){
std::string vertex1, vertex2, vertex3;
unsigned int vertexIndex[3], uvIndex[3], normalIndex[3];
int matches = fscanf(file, "%d/%d/%d %d/%d/%d %d/%d/%d\n", &vertexIndex[0], &uvIndex[0], &normalIndex[0], &vertexIndex[1], &uvIndex[1], &normalIndex[1], &vertexIndex[2], &uvIndex[2], &normalIndex[2] );
vertexIndices.push_back(vertexIndex[0]);
vertexIndices.push_back(vertexIndex[1]);
vertexIndices.push_back(vertexIndex[2]);
uvIndices .push_back(uvIndex[0]);
uvIndices .push_back(uvIndex[1]);
uvIndices .push_back(uvIndex[2]);
normalIndices.push_back(normalIndex[0]);
normalIndices.push_back(normalIndex[1]);
normalIndices.push_back(normalIndex[2]);
}else{
char stupidBuffer[1000];
fgets(stupidBuffer, 1000, file);
}
}
for( unsigned int i=0; i<vertexIndices.size(); i++ ){
unsigned int vertexIndex = vertexIndices[i];
unsigned int uvIndex = uvIndices[i];
unsigned int normalIndex = normalIndices[i];
glm::vec3 vertex = temp_vertices[ vertexIndex-1 ];
glm::vec2 uv = temp_uvs[ uvIndex-1 ];
glm::vec3 normal = temp_normals[ normalIndex-1 ];
out_vertices.push_back(vertex);
out_uvs .push_back(uv);
out_normals .push_back(normal);
}
return true;
}
Update:
adding some pictures of what it should look like and my drawing code.
this is what it should look like:
this is what it actually looks like:
Update 2: adding my shader code due to a request in the comments sorry about this becoming a massive wall of text also in_Color is treated as a uv I just haven't renamed it yet. vertex shader:
#version 150 core
uniform mat4 M;
uniform mat4 MVP;
uniform vec3 LightPosition_worldspace;
uniform mat4 V;
in vec3 in_Position;
in vec2 in_Color;
in vec3 in_Normals;
out vec2 pass_Color;
out vec3 Position_worldspace;
out vec3 Normal_cameraspace;
out vec3 EyeDirection_cameraspace;
out vec3 LightDirection_cameraspace;
void main(void)
{
gl_Position = MVP* vec4(in_Position, 1.0);
Position_worldspace = (M * vec4(in_Position,1)).xyz;
vec3 vertexPosition_cameraspace = ( V * M * vec4(in_Position,1)).xyz;
EyeDirection_cameraspace = vec3(0,0,0) - vertexPosition_cameraspace;
vec3 LightPosition_cameraspace = ( V * vec4(LightPosition_worldspace,1)).xyz;
Normal_cameraspace = ( V * M * vec4(in_Normals,0)).xyz;
pass_Color = in_Color;
}
fragment shader:
#version 150 core
in vec2 pass_Color;
in vec3 Position_worldspace;
in vec3 Normal_cameraspace;
in vec3 EyeDirection_cameraspace;
in vec3 LightDirection_cameraspace;
out vec3 out_Color;
uniform sampler2D myTextureSampler;
uniform mat4 MV;
uniform vec3 LightPosition_worldspace;
void main(void)
{
vec3 LightColor = vec3(1,1,1);
float LightPower = 200.0f;
vec3 MaterialDiffuseColor = texture2D( myTextureSampler, pass_Color ).rgb;
vec3 MaterialAmbientColor = vec3(0.1,0.1,0.1) * MaterialDiffuseColor;
vec3 MaterialSpecularColor = vec3(0.3,0.3,0.3);
float distance = length( LightPosition_worldspace - Position_worldspace );
vec3 n = normalize( Normal_cameraspace );
vec3 l = normalize( LightDirection_cameraspace );
float cosTheta = clamp( dot( n,l ), 0,1 );
vec3 E = normalize(EyeDirection_cameraspace);
vec3 R = reflect(-l,n);
float cosAlpha = clamp( dot( E,R ), 0,1 );
out_Color = MaterialAmbientColor
+ MaterialDiffuseColor * LightColor * LightPower
* cosTheta / (distance*distance) +MaterialSpecularColor
* LightColor * LightPower * pow(cosAlpha,5) / (distance*distance);
}
