//=================================================== mouse2plane
//===============================================================
void TFWidgetRen::mouse2plane(int x, int y)
{
// assume we are always aligned with z axis
// should be based on up vector and (at-eye)xup vector!!!!!
float fx = 1 - (float)x/(float)gluvv.win.width;
float fy = (float)(gluvv.win.height - y)/(float)gluvv.win.height;
float vdir[3];
subV3(vdir, gluvv.env.at, gluvv.env.eye);
normalizeV3(vdir);
scaleV3(gluvv.env.clip[0], vdir);
float fcp[3]; //position of front clipping plane
addV3(fcp, gluvv.env.eye, vdir);
float cpnt[3];//clip plane point (projecton of screen point on clip plane)
cpnt[0] = ((fcp[0] + gluvv.env.frustum[0]) +
(gluvv.env.frustum[1] - gluvv.env.frustum[0]) * fx);
cpnt[1] = ((fcp[1] + gluvv.env.frustum[2]) +
(gluvv.env.frustum[3] - gluvv.env.frustum[2]) * fy);
cpnt[2] = fcp[2]; //remember, assume z aligned view direction
float ep[3]; //eye - pos
subV3(ep, gluvv.env.eye, pos);
float me[3]; //eye - clipplane point
subV3(me, gluvv.env.eye, cpnt);
float dir[3] = {0,0,-1};
float t = dotV3(dir, ep)/dotV3(dir, me);
negateV3(me);
scaleV3(t,me);
addV3(mousepnt, me, gluvv.env.eye);
}
void uniqueMap(obj* object) {
int i, j, k;
int vIndices[3], tIndices[3];
for(i = 0; i < object->faceCount; ++i) {
for(j = 0; j < 3; ++j) {
vIndices[j] = object->faces[i][j][0] - 1;
tIndices[j] = object->faces[i][j][1] - 1;
}
for(j = 0; j < 3; ++j) {
vec3 V[3];
vec2 T[3];
for(k = 0; k < 3; ++k) {
V[k] = object->vertices[vIndices[(j+k)%3]];
T[k] = object->textures[tIndices[(j+k)%3]];
}
vec3 edge1 = subV3(V[1], V[0]);
vec3 edge2 = subV3(V[2], V[0]);
vec2 deltaUV1 = subV2(T[1], T[0]);
vec2 deltaUV2 = subV2(T[2], T[0]);
GLfloat f = 1.0f / (deltaUV1.x * deltaUV2.y - deltaUV2.x * deltaUV1.y);
vec3 tangent;
tangent.x = f * (deltaUV2.y * edge1.x - deltaUV1.y * edge2.x);
tangent.y = f * (deltaUV2.y * edge1.y - deltaUV1.y * edge2.y);
tangent.z = f * (deltaUV2.y * edge1.z - deltaUV1.y * edge2.z);
tangent = unit(tangent);
vec3 bitangent;
bitangent.x = f * (-deltaUV2.x * edge1.x + deltaUV1.x * edge2.x);
bitangent.y = f * (-deltaUV2.x * edge1.y + deltaUV1.x * edge2.y);
bitangent.z = f * (-deltaUV2.x * edge1.z + deltaUV1.x * edge2.z);
bitangent = unit(bitangent);
object->tangents[vIndices[j]] = addV3(object->tangents[vIndices[j]], tangent);
object->bitangents[vIndices[j]] = addV3(object->bitangents[vIndices[j]], bitangent);
}
for(j = 0; j < 3; ++j) ++object->shared[vIndices[j]];
}
for(i = 0; i < object->vertexCount; ++i) {
object->tangents[i] = unit(scale(object->tangents[i], 1.0f / object->shared[i]));
object->bitangents[i] = unit(scale(object->bitangents[i], 1.0f / object->shared[i]));
}
}
