///////////////////////////////////////////////////////////////////////////////////////
// Get Window coordinates, discard Z...
void m3dProjectXY(M3DVector2f vPointOut, const M3DMatrix44f mModelView, const M3DMatrix44f mProjection, const int iViewPort[4], const M3DVector3f vPointIn)
{
M3DVector4f vBack, vForth;
memcpy(vBack, vPointIn, sizeof(float)*3);
vBack[3] = 1.0f;
m3dTransformVector4(vForth, vBack, mModelView);
m3dTransformVector4(vBack, vForth, mProjection);
if(!m3dCloseEnough(vBack[3], 0.0f, 0.000001f)) {
float div = 1.0f / vBack[3];
vBack[0] *= div;
vBack[1] *= div;
//vBack[2] *= div;
}
vPointOut[0] = float(iViewPort[0])+(1.0f+float(vBack[0]))*float(iViewPort[2])/2.0f;
vPointOut[1] = float(iViewPort[1])+(1.0f+float(vBack[1]))*float(iViewPort[3])/2.0f;
// This was put in for Grand Tour... I think it's right.
// .... please report any bugs
if(iViewPort[0] != 0) // Cast to float is expensive... avoid if posssible
vPointOut[0] -= float(iViewPort[0]);
if(iViewPort[1] != 0)
vPointOut[1] -= float(iViewPort[1]);
}
///////////////////////////////////////////////////////////////////////////////////////
// Get window coordinates, we also want Z....
void m3dProjectXYZ(M3DVector3f vPointOut, const M3DMatrix44f mModelView, const M3DMatrix44f mProjection, const int iViewPort[4], const M3DVector3f vPointIn)
{
M3DVector4f vBack, vForth;
memcpy(vBack, vPointIn, sizeof(float)*3);
vBack[3] = 1.0f;
m3dTransformVector4(vForth, vBack, mModelView);
m3dTransformVector4(vBack, vForth, mProjection);
if(!m3dCloseEnough(vBack[3], 0.0f, 0.000001f)) {
float div = 1.0f / vBack[3];
vBack[0] *= div;
vBack[1] *= div;
vBack[2] *= div;
}
vPointOut[0] = float(iViewPort[0])+(1.0f+float(vBack[0]))*float(iViewPort[2])/2.0f;
vPointOut[1] = float(iViewPort[1])+(1.0f+float(vBack[1]))*float(iViewPort[3])/2.0f;
if(iViewPort[0] != 0) // Cast to float is expensive... avoid if posssible
vPointOut[0] -= float(iViewPort[0]);
if(iViewPort[1] != 0)
vPointOut[1] -= float(iViewPort[1]);
vPointOut[2] = vBack[2];
}
///////////////////////////////////////////////////////////////////////////////////////
// Get window coordinates, we also want Z....
void m3dProjectXYZ(const M3DMatrix44f mModelView, const M3DMatrix44f mProjection, const int iViewPort[4], const M3DVector3f vPointIn, M3DVector3f vPointOut)
{
M3DVector4f vBack, vForth;
memcpy(vBack, vPointIn, sizeof(float)*3);
vBack[3] = 1.0f;
m3dTransformVector4(vForth, vBack, mModelView);
m3dTransformVector4(vBack, vForth, mProjection);
if(!m3dCloseEnough(vBack[3], 0.0f, 0.000001f)) {
float div = 1.0f / vBack[3];
vBack[0] *= div;
vBack[1] *= div;
vBack[2] *= div;
}
vPointOut[0] = vBack[0] * 0.5f + 0.5f;
vPointOut[1] = vBack[1] * 0.5f + 0.5f;
vPointOut[2] = vBack[2] * 0.5f + 0.5f;
/* Map x,y to viewport */
vPointOut[0] = (vPointOut[0] * iViewPort[2]) + iViewPort[0];
vPointOut[1] = (vPointOut[1] * iViewPort[3]) + iViewPort[1];
}
/////////////////////////////////////////////////////////////////
// Add a triangle to the mesh. This searches the current list for identical
// (well, almost identical - these are floats you know...) verts. If one is found, it
// is added to the index array. If not, it is added to both the index array and the vertex
// array grows by one as well.
void CVBOMesh::AddTriangle(M3DVector3f verts[3], M3DVector3f vNorms[3], M3DVector2f vTexCoords[3])
{
const float e = 0.000001; // How small a difference to equate
// First thing we do is make sure the normals are unit length!
// It's almost always a good idea to work with pre-normalized normals
m3dNormalizeVector(vNorms[0]);
m3dNormalizeVector(vNorms[1]);
m3dNormalizeVector(vNorms[2]);
// Search for match - triangle consists of three verts
for(GLuint iVertex = 0; iVertex < 3; iVertex++)
{
GLuint iMatch = 0;
for(iMatch = 0; iMatch < nNumVerts; iMatch++)
{
// If the vertex positions are the same
if(m3dCloseEnough(pVerts[iMatch][0], verts[iVertex][0], e) &&
m3dCloseEnough(pVerts[iMatch][1], verts[iVertex][1], e) &&
m3dCloseEnough(pVerts[iMatch][2], verts[iVertex][2], e) &&
// AND the Normal is the same...
m3dCloseEnough(pNorms[iMatch][0], vNorms[iVertex][0], e) &&
m3dCloseEnough(pNorms[iMatch][1], vNorms[iVertex][1], e) &&
m3dCloseEnough(pNorms[iMatch][2], vNorms[iVertex][2], e) &&
// And Texture is the same...
m3dCloseEnough(pTexCoords[iMatch][0], vTexCoords[iVertex][0], e) &&
m3dCloseEnough(pTexCoords[iMatch][1], vTexCoords[iVertex][1], e))
{
// Then add the index only
pIndexes[nNumIndexes] = iMatch;
nNumIndexes++;
break;
}
}
// No match for this vertex, add to end of list
if(iMatch == nNumVerts)
{
memcpy(pVerts[nNumVerts], verts[iVertex], sizeof(M3DVector3f));
memcpy(pNorms[nNumVerts], vNorms[iVertex], sizeof(M3DVector3f));
memcpy(pTexCoords[nNumVerts], &vTexCoords[iVertex], sizeof(M3DVector2f));
pIndexes[nNumIndexes] = nNumVerts;
nNumIndexes++;
nNumVerts++;
}
}
}
// Draw a cylinder. Much like gluCylinder
void gltMakeCylinder(GLTriangleBatch& cylinderBatch, GLfloat baseRadius, GLfloat topRadius,
GLfloat fLength, GLint numSlices, GLint numStacks)
{
float fRadiusStep = (topRadius - baseRadius) / float(numStacks);
GLfloat fStepSizeSlice = (3.1415926536f * 2.0f) / float(numSlices);
M3DVector3f vVertex[4];
M3DVector3f vNormal[4];
M3DVector2f vTexture[4];
cylinderBatch.BeginMesh(numSlices * numStacks * 6);
GLfloat ds = 1.0f / float(numSlices);
GLfloat dt = 1.0f / float(numStacks);
GLfloat s;
GLfloat t;
for (int i = 0; i < numStacks; i++)
{
if(i == 0)
t = 0.0f;
else
t = float(i) * dt;
float tNext;
if(i == (numStacks - 1))
tNext = 1.0f;
else
tNext = float(i+1) * dt;
float fCurrentRadius = baseRadius + (fRadiusStep * float(i));
float fNextRadius = baseRadius + (fRadiusStep * float(i+1));
float theyta;
float theytaNext;
float fCurrentZ = float(i) * (fLength / float(numStacks));
float fNextZ = float(i+1) * (fLength / float(numStacks));
float zNormal = 0.0f;
if(!m3dCloseEnough(baseRadius - topRadius, 0.0f, 0.00001f))
{
// Rise over run...
zNormal = (baseRadius - topRadius);
}
for (int j = 0; j < numSlices; j++)
{
if(j == 0)
s = 0.0f;
else
s = float(j) * ds;
float sNext;
if(j == (numSlices -1))
sNext = 1.0f;
else
sNext = float(j+1) * ds;
theyta = fStepSizeSlice * float(j);
if(j == (numSlices - 1))
theytaNext = 0.0f;
else
theytaNext = fStepSizeSlice * (float(j+1));
// Inner First
vVertex[1][0] = cos(theyta) * fCurrentRadius; // X
vVertex[1][1] = sin(theyta) * fCurrentRadius; // Y
vVertex[1][2] = fCurrentZ; // Z
vNormal[1][0] = vVertex[1][0]; // Surface Normal, same for everybody
vNormal[1][1] = vVertex[1][1];
vNormal[1][2] = zNormal;
m3dNormalizeVector3(vNormal[1]);
vTexture[1][0] = s; // Texture Coordinates, I have no idea...
vTexture[1][1] = t;
// Outer First
vVertex[0][0] = cos(theyta) * fNextRadius; // X
vVertex[0][1] = sin(theyta) * fNextRadius; // Y
vVertex[0][2] = fNextZ; // Z
if(!m3dCloseEnough(fNextRadius, 0.0f, 0.00001f)) {
vNormal[0][0] = vVertex[0][0]; // Surface Normal, same for everybody
vNormal[0][1] = vVertex[0][1]; // For cones, tip is tricky
vNormal[0][2] = zNormal;
m3dNormalizeVector3(vNormal[0]);
}
else
memcpy(vNormal[0], vNormal[1], sizeof(M3DVector3f));
vTexture[0][0] = s; // Texture Coordinates, I have no idea...
vTexture[0][1] = tNext;
// Inner second
vVertex[3][0] = cos(theytaNext) * fCurrentRadius; // X
vVertex[3][1] = sin(theytaNext) * fCurrentRadius; // Y
vVertex[3][2] = fCurrentZ; // Z
vNormal[3][0] = vVertex[3][0]; // Surface Normal, same for everybody
vNormal[3][1] = vVertex[3][1];
vNormal[3][2] = zNormal;
m3dNormalizeVector3(vNormal[3]);
vTexture[3][0] = sNext; // Texture Coordinates, I have no idea...
vTexture[3][1] = t;
// Outer second
vVertex[2][0] = cos(theytaNext) * fNextRadius; // X
vVertex[2][1] = sin(theytaNext) * fNextRadius; // Y
vVertex[2][2] = fNextZ; // Z
if(!m3dCloseEnough(fNextRadius, 0.0f, 0.00001f)) {
vNormal[2][0] = vVertex[2][0]; // Surface Normal, same for everybody
vNormal[2][1] = vVertex[2][1];
vNormal[2][2] = zNormal;
m3dNormalizeVector3(vNormal[2]);
}
else
memcpy(vNormal[2], vNormal[3], sizeof(M3DVector3f));
vTexture[2][0] = sNext; // Texture Coordinates, I have no idea...
vTexture[2][1] = tNext;
cylinderBatch.AddTriangle(vVertex, vNormal, vTexture);
// Rearrange for next triangle
memcpy(vVertex[0], vVertex[1], sizeof(M3DVector3f));
memcpy(vNormal[0], vNormal[1], sizeof(M3DVector3f));
memcpy(vTexture[0], vTexture[1], sizeof(M3DVector2f));
memcpy(vVertex[1], vVertex[3], sizeof(M3DVector3f));
memcpy(vNormal[1], vNormal[3], sizeof(M3DVector3f));
memcpy(vTexture[1], vTexture[3], sizeof(M3DVector2f));
cylinderBatch.AddTriangle(vVertex, vNormal, vTexture);
}
}
cylinderBatch.End();
}
