U32 LLVOTree::drawBranchPipeline(LLMatrix4& matrix, U16* indicesp, S32 trunk_LOD, S32 stop_level, U16 depth, U16 trunk_depth, F32 scale, F32 twist, F32 droop, F32 branches, F32 alpha)
{
U32 ret = 0;
//
// Draws a tree by recursing, drawing branches and then a 'leaf' texture.
// If stop_level = -1, simply draws the whole tree as a billboarded texture
//
static F32 constant_twist;
static F32 width = 0;
//F32 length = ((scale == 1.f)? mTrunkLength:mBranchLength);
//F32 aspect = ((scale == 1.f)? mTrunkAspect:mBranchAspect);
F32 length = ((trunk_depth || (scale == 1.f))? mTrunkLength:mBranchLength);
F32 aspect = ((trunk_depth || (scale == 1.f))? mTrunkAspect:mBranchAspect);
constant_twist = 360.f/branches;
if (!LLPipeline::sReflectionRender && stop_level >= 0)
{
//
// Draw the tree using recursion
//
if (depth > stop_level)
{
{
llassert(sLODIndexCount[trunk_LOD] > 0);
width = scale * length * aspect;
LLMatrix4 scale_mat;
scale_mat.mMatrix[0][0] = width;
scale_mat.mMatrix[1][1] = width;
scale_mat.mMatrix[2][2] = scale*length;
scale_mat *= matrix;
glLoadMatrixf((F32*) scale_mat.mMatrix);
glDrawElements(GL_TRIANGLES, sLODIndexCount[trunk_LOD], GL_UNSIGNED_SHORT, indicesp + sLODIndexOffset[trunk_LOD]);
gPipeline.addTrianglesDrawn(LEAF_INDICES/3);
stop_glerror();
ret += sLODIndexCount[trunk_LOD];
}
// Recurse to create more branches
for (S32 i=0; i < (S32)branches; i++)
{
LLMatrix4 trans_mat;
trans_mat.setTranslation(0,0,scale*length);
trans_mat *= matrix;
LLQuaternion rot =
LLQuaternion(20.f*DEG_TO_RAD, LLVector4(0.f, 0.f, 1.f)) *
LLQuaternion(droop*DEG_TO_RAD, LLVector4(0.f, 1.f, 0.f)) *
LLQuaternion(((constant_twist + ((i%2==0)?twist:-twist))*i)*DEG_TO_RAD, LLVector4(0.f, 0.f, 1.f));
LLMatrix4 rot_mat(rot);
rot_mat *= trans_mat;
ret += drawBranchPipeline(rot_mat, indicesp, trunk_LOD, stop_level, depth - 1, 0, scale*mScaleStep, twist, droop, branches, alpha);
}
// Recurse to continue trunk
if (trunk_depth)
{
LLMatrix4 trans_mat;
trans_mat.setTranslation(0,0,scale*length);
trans_mat *= matrix;
LLMatrix4 rot_mat(70.5f*DEG_TO_RAD, LLVector4(0,0,1));
rot_mat *= trans_mat; // rotate a bit around Z when ascending
ret += drawBranchPipeline(rot_mat, indicesp, trunk_LOD, stop_level, depth, trunk_depth-1, scale*mScaleStep, twist, droop, branches, alpha);
}
}
else
{
//
// Draw leaves as two 90 deg crossed quads with leaf textures
//
{
LLMatrix4 scale_mat;
scale_mat.mMatrix[0][0] =
scale_mat.mMatrix[1][1] =
scale_mat.mMatrix[2][2] = scale*mLeafScale;
scale_mat *= matrix;
glLoadMatrixf((F32*) scale_mat.mMatrix);
glDrawElements(GL_TRIANGLES, LEAF_INDICES, GL_UNSIGNED_SHORT, indicesp);
gPipeline.addTrianglesDrawn(LEAF_INDICES/3);
stop_glerror();
ret += LEAF_INDICES;
}
}
}
else
{
//
// Draw the tree as a single billboard texture
//
LLMatrix4 scale_mat;
scale_mat.mMatrix[0][0] =
scale_mat.mMatrix[1][1] =
scale_mat.mMatrix[2][2] = mBillboardScale*mBillboardRatio;
scale_mat *= matrix;
glMatrixMode(GL_TEXTURE);
glTranslatef(0.0, -0.5, 0.0);
glMatrixMode(GL_MODELVIEW);
glLoadMatrixf((F32*) scale_mat.mMatrix);
glDrawElements(GL_TRIANGLES, LEAF_INDICES, GL_UNSIGNED_SHORT, indicesp);
gPipeline.addTrianglesDrawn(LEAF_INDICES/3);
stop_glerror();
ret += LEAF_INDICES;
glMatrixMode(GL_TEXTURE);
glLoadIdentity();
glMatrixMode(GL_MODELVIEW);
}
return ret;
}
