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lummxx
04-16-2016, 05:56 PM
I have a rotation problems.

I have the camera set up so that up vector is Z, -X is forward and right is Y. I have models that are exported in another coordinate system where Y is up, -Z is forward, X is right.

My challenge/problem is with rotation. How to do correct rotation in this case without changing the coordinate system of objects that I import. Scale and transform are working as they should.

So far I have tried swapping Y and Z axis in the rotation matrix manual, doing the rotation matrix separately, doing the rotation as we read control file, flipping Z and Y rotation axis, changing the matrix to

| 1 0 0 |
| 0 0 1 |
| 0 1 0 |

etc.

PS. I dont want to change the coordinate system of the object files that I import now and when I write in the control file rotateY it will rotate the object in my Y axis not the object Y axis.

This is the part of code I am trying the transformations



for(int i = 0; i< controls.size(); i++) {
meshStruct tempMesh;

int isMeshLoaded = loadObjFile((char*)controls[i].path, &tempMesh.objectInfo_, &tempMesh.numObjects_);
if(isMeshLoaded)
{
cout<< "Mesh " << controls[i].path << " loaded sucesfully." << endl;
} else {
cout<< "Mesh " << controls[i].path << " loaded failed." << endl;
}

tempModelMatrix = mat4(1.0f, 0.0f, 0.0f, 0.0f,
0.0f, 1.0f, 0.0f, 0.0f,
0.0f, 0.0f, 1.0f, 0.0f,
0.0f, 0.0f, 0.0f, 1.0f);

//mat4 tempModelMatrixFlip = mat4(1.0f, 0.0f, 0.0f, 0.0f,
// 0.0f, 0.0f, 1.0f, 0.0f,
// 0.0f, 1.0f, 0.0f, 0.0f,
// 0.0f, 0.0f, 0.0f, 1.0f);
//tempModelMatrix *= tempModelMatrixFlip;

tempModelMatrix = glm::translate(tempModelMatrix, controls[i].translate);

tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.x), vec3(1.0, 0.0, 0.0));
tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.y), vec3(0.0, 1.0, 0.0));
tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.z), vec3(0.0, 0.0, 1.0));

mat4 r = mat4(1.0f);
mat4 rx = mat4(1.0f);
mat4 ry = mat4(1.0f);
mat4 rz = mat4(1.0f);
rx = rotate(radians(controls[i].rotation.x), vec3(1.0, 0.0, 0.0));
ry = rotate(radians(controls[i].rotation.y), vec3(0.0, 1.0, 0.0));
rz = rotate(radians(controls[i].rotation.z), vec3(0.0, 0.0, 1.0));
r = rx * ry * rz;
/*
vec4 temp;

temp = column(r, 1);
cout << to_string(temp) << endl;
r = column(r,1, column(r, 2));
r = column(r,2, temp);

temp = row(r,1);
r = row(r, 1,row(r,2));
r = row(r, 2, temp);
//cout << to_string(column(tempModelMatrix, 1)) << endl;

//tempModelMatrix *= r;
float tempModelMatrix2[16];// = mat4(1.0f);

tempModelMatrix2[0] = controls[i].scale.x * column(r, 0).x;//controls[i].scale.x * controls[i].rotation.x;
tempModelMatrix2[1] = controls[i].scale.x * column(r, 0).y;//controls[i].scale.x * controls[i].rotation.x;
tempModelMatrix2[2] = controls[i].scale.x * column(r, 0).z;//controls[i].scale.x * controls[i].rotation.x;
tempModelMatrix2[3] = 0.0f;
tempModelMatrix2[4] = controls[i].scale.y * column(r, 2).x;//controls[i].scale.y * controls[i].rotation.y;
tempModelMatrix2[5] = controls[i].scale.y * column(r, 2).y;//controls[i].scale.y * controls[i].rotation.y;
tempModelMatrix2[6] = controls[i].scale.y * column(r, 2).z;//controls[i].scale.y * controls[i].rotation.y;
tempModelMatrix2[7] = 0.0f;
tempModelMatrix2[8] = controls[i].scale.z * column(r, 1).x;//controls[i].scale.z * controls[i].rotation.z;
tempModelMatrix2[9] = controls[i].scale.z * column(r, 1).y;//controls[i].scale.z * controls[i].rotation.z;
tempModelMatrix2[10] = controls[i].scale.z * column(r, 1).z;//controls[i].scale.z * controls[i].rotation.z;
tempModelMatrix2[11] = 0.0f;
tempModelMatrix2[12] = controls[i].translate.x;
tempModelMatrix2[13] = controls[i].translate.y;
tempModelMatrix2[14] = controls[i].translate.z;
tempModelMatrix2[15] = 1.0f;*/

tempModelMatrix = glm::scale(tempModelMatrix, controls[i].scale);
//cout << controls[i].path << " controls[i].translate " << to_string(controls[i].translate) << endl;
//cout << controls[i].path << " controls[i].rotation.X " << controls[i].rotation.x << endl;
//cout << controls[i].path << " controls[i].rotation.y " << controls[i].rotation.y << endl;
//cout << controls[i].path << " controls[i].rotation.Z " << controls[i].rotation.z << endl;
//cout << controls[i].path << " controls[i].scale " << to_string(controls[i].scale) << endl;

string basedir = dirname(controls[i].path);
for(int j = 0; j < tempMesh.numObjects_; j++){
//tempMesh.objectInfo_[j].modelMatrix = controls[i].modelMatrix;
tempMesh.objectInfo_[j].modelMatrix = tempModelMatrix;
//tempMesh.objectInfo_[j].modelMatrix = make_mat4(tempModelMatrix2);

lummxx
04-16-2016, 08:42 PM
Fixed the problem after going through some emails with the professor and had a small error when calculating rotation matrix. I was doing it in the reverse way


tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.x), vec3(1.0, 0.0, 0.0));
tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.y), vec3(0.0, 1.0, 0.0));
tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.z), vec3(0.0, 0.0, 1.0));

instead of


tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.z), vec3(0.0, 0.0, 1.0));
tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.y), vec3(0.0, 1.0, 0.0));
tempModelMatrix = glm::rotate(tempModelMatrix, radians(controls[i].rotation.x), vec3(1.0, 0.0, 0.0));

Thanks