open_toontown_panda3d/panda/src/pgraph/cullResult.cxx

352 lines
14 KiB
C++

// Filename: cullResult.cxx
// Created by: drose (28Feb02)
//
////////////////////////////////////////////////////////////////////
//
// PANDA 3D SOFTWARE
// Copyright (c) 2001, Disney Enterprises, Inc. All rights reserved
//
// All use of this software is subject to the terms of the Panda 3d
// Software license. You should have received a copy of this license
// along with this source code; you will also find a current copy of
// the license at http://www.panda3d.org/license.txt .
//
// To contact the maintainers of this program write to
// panda3d@yahoogroups.com .
//
////////////////////////////////////////////////////////////////////
#include "cullResult.h"
#include "cullBinManager.h"
#include "alphaTestAttrib.h"
#include "transparencyAttrib.h"
#include "renderState.h"
#include "clockObject.h"
// This value is used instead of 1.0 to represent the alpha level of a
// pixel that is to be considered "opaque" for the purposes of M_dual.
// Ideally, 1.0 is the only correct value for this. Realistically, we
// have to fudge it lower for two reasons:
// (1) The modelers tend to paint textures with very slight
// transparency levels in places that are not intended to be
// transparent, without realizing it. These very faint transparency
// regions are normally (almost) invisible, but when rendered with
// M_dual they may be revealed as regions of poor alpha sorting.
// (2) There seems to be some problem in DX where, in certain
// circumstances apparently related to automatic texture management,
// it spontaneously drops out the bottom two bits of an eight-bit
// alpha channel, causing a value of 255 to become a value of 252
// instead.
// We use 256 as the denominator here (instead of, say, 255) because a
// fractional power of two will have a terminating representation in
// base 2, and thus will be more likely to have a precise value in
// whatever internal representation the graphics API will use.
static const float dual_opaque_level = 252.0f / 256.0f;
////////////////////////////////////////////////////////////////////
// Function: CullResult::make_next
// Access: Public
// Description: Returns a newly-allocated CullResult object that
// contains a copy of just the subset of the data from
// this CullResult object that is worth keeping around
// for next frame.
////////////////////////////////////////////////////////////////////
PT(CullResult) CullResult::
make_next() const {
PT(CullResult) new_result = new CullResult(_gsg);
new_result->_bins.reserve(_bins.size());
for (Bins::const_iterator bi = _bins.begin(); bi != _bins.end(); ++bi) {
CullBin *old_bin = (*bi);
if (old_bin == (CullBin *)NULL) {
new_result->_bins.push_back((CullBin *)NULL);
} else {
new_result->_bins.push_back(old_bin->make_next());
}
}
return new_result;
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::add_object
// Access: Public
// Description: Adds the indicated CullableObject to the appropriate
// bin. The bin becomes the owner of the object
// pointer, and will eventually delete it.
////////////////////////////////////////////////////////////////////
void CullResult::
add_object(CullableObject *object) {
// Check to see if there's a special transparency setting.
const RenderState *state = object->_state;
nassertv(state != (const RenderState *)NULL);
const TransparencyAttrib *trans = state->get_transparency();
if (trans != (const TransparencyAttrib *)NULL) {
switch (trans->get_mode()) {
case TransparencyAttrib::M_binary:
// M_binary is implemented by explicitly setting the alpha test.
object->_state = state->compose(get_binary_state());
break;
case TransparencyAttrib::M_dual:
if (m_dual) {
// M_dual is implemented by drawing the opaque parts first,
// without transparency, then drawing the transparent parts
// later. This means we must copy the object and add it to
// both bins. We can only do this if we do not have an
// explicit bin already applied; otherwise, M_dual falls back
// to M_alpha.
const CullBinAttrib *bin_attrib = state->get_bin();
if (bin_attrib == (CullBinAttrib *)NULL ||
bin_attrib->get_bin_name().empty()) {
// We make a copy of the object to draw the transparent part
// without decals; this gets placed in the transparent bin.
#ifndef NDEBUG
if (m_dual_transparent)
#endif
{
CullableObject *transparent_part = new CullableObject(*object);
CPT(RenderState) transparent_state = object->has_decals() ?
get_dual_transparent_state_decals() :
get_dual_transparent_state();
transparent_part->_state = state->compose(transparent_state);
CullBin *bin = get_bin(transparent_part->_state->get_bin_index());
nassertv(bin != (CullBin *)NULL);
bin->add_object(transparent_part);
}
// Now we can draw the opaque part, with decals. This will
// end up in the opaque bin.
object->_state = state->compose(get_dual_opaque_state());
#ifndef NDEBUG
if (!m_dual_opaque) {
delete object;
return;
}
#endif
}
}
break;
default:
// Other kinds of transparency need no special handling.
break;
}
}
CullBin *bin = get_bin(object->_state->get_bin_index());
nassertv(bin != (CullBin *)NULL);
bin->add_object(object);
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::finish_cull
// Access: Public
// Description: Called after all the geoms have been added, this
// indicates that the cull process is finished for this
// frame and gives the bins a chance to do any
// post-processing (like sorting) before moving on to
// draw.
////////////////////////////////////////////////////////////////////
void CullResult::
finish_cull() {
for (Bins::iterator bi = _bins.begin(); bi != _bins.end(); ++bi) {
CullBin *bin = (*bi);
if (bin != (CullBin *)NULL) {
bin->finish_cull();
}
}
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::draw
// Access: Public
// Description: Asks all the bins to draw themselves in the correct
// order.
////////////////////////////////////////////////////////////////////
void CullResult::
draw() {
// Ask the bin manager for the correct order to draw all the bins.
CullBinManager *bin_manager = CullBinManager::get_global_ptr();
int num_bins = bin_manager->get_num_bins();
for (int i = 0; i < num_bins; i++) {
int bin_index = bin_manager->get_bin(i);
nassertv(bin_index >= 0);
if (bin_index < (int)_bins.size() && _bins[bin_index] != (CullBin *)NULL) {
_bins[bin_index]->draw();
}
}
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::bin_removed
// Access: Public, Static
// Description: Intended to be called by
// CullBinManager::remove_bin(), this informs all the
// CullResults in the world to remove the indicated
// bin_index from their cache if it has been cached.
////////////////////////////////////////////////////////////////////
void CullResult::
bin_removed(int bin_index) {
// Do something here.
nassertv(false);
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::make_new_bin
// Access: Private
// Description: Allocates a new CullBin for the given bin_index and
// stores it for next time.
////////////////////////////////////////////////////////////////////
CullBin *CullResult::
make_new_bin(int bin_index) {
CullBinManager *bin_manager = CullBinManager::get_global_ptr();
PT(CullBin) bin = bin_manager->make_new_bin(bin_index, _gsg);
if (bin != (CullBin *)NULL) {
// Now store it in the vector.
while (bin_index >= (int)_bins.size()) {
_bins.push_back((CullBin *)NULL);
}
nassertr(bin_index >= 0 && bin_index < (int)_bins.size(), NULL);
_bins[bin_index] = bin;
}
return bin;
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::get_binary_state
// Access: Private
// Description: Returns a RenderState that applies the effects of
// M_binary.
////////////////////////////////////////////////////////////////////
CPT(RenderState) CullResult::
get_binary_state() {
static CPT(RenderState) state = NULL;
if (state == (const RenderState *)NULL) {
state = RenderState::make(AlphaTestAttrib::make(AlphaTestAttrib::M_greater_equal, 0.5f),
TransparencyAttrib::make(TransparencyAttrib::M_none),
RenderState::get_max_priority());
}
return state;
}
#ifndef NDEBUG
static const double m_dual_flash_rate = 1.0; // 1 state change per second
#endif
////////////////////////////////////////////////////////////////////
// Function: CullResult::get_dual_transparent_state
// Access: Private
// Description: Returns a RenderState that renders only the
// transparent parts of an object, in support of M_dual.
// This state is suitable only for objects that do not
// contain decals.
////////////////////////////////////////////////////////////////////
CPT(RenderState) CullResult::
get_dual_transparent_state() {
static CPT(RenderState) state = NULL;
if (state == (const RenderState *)NULL) {
// The alpha test for > 0 prevents us from drawing empty pixels,
// and hence filling up the depth buffer with large empty spaces
// that may obscure other things. However, this does mean we draw
// pixels twice where the alpha == 1.0 (since they were already
// drawn in the opaque pass). This is not normally a problem,
// except when we are using decals; in the case of decals, we
// don't want to draw the 1.0 pixels again, since these are the
// ones that may have been decaled onto.
state = RenderState::make(AlphaTestAttrib::make(AlphaTestAttrib::M_greater, 0.0f),
TransparencyAttrib::make(TransparencyAttrib::M_alpha),
RenderState::get_max_priority());
}
#ifndef NDEBUG
if (m_dual_flash) {
int cycle = (int)(ClockObject::get_global_clock()->get_real_time() * m_dual_flash_rate);
if ((cycle & 1) == 0) {
static CPT(RenderState) flash_state = NULL;
if (flash_state == (const RenderState *)NULL) {
flash_state = state->add_attrib(ColorScaleAttrib::make(LVecBase4f(0.8f, 0.2f, 0.2f, 1.0f)));
flash_state = flash_state->add_attrib(AlphaTestAttrib::make(AlphaTestAttrib::M_less, 1.0f));
}
return flash_state;
}
}
#endif // NDEBUG
return state;
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::get_dual_transparent_state_decals
// Access: Private
// Description: Returns a RenderState that renders only the
// transparent parts of an object, but suitable for
// objects that contain decals.
////////////////////////////////////////////////////////////////////
CPT(RenderState) CullResult::
get_dual_transparent_state_decals() {
static CPT(RenderState) state = NULL;
if (state == (const RenderState *)NULL) {
// This is exactly the same as above except here we make the alpha
// test of < 1.0 instead of > 0.0. This makes us draw big empty
// pixels where the alpha values are 0.0, but we don't overwrite
// the decals where the pixels are 1.0.
state = RenderState::make(AlphaTestAttrib::make(AlphaTestAttrib::M_less, dual_opaque_level),
TransparencyAttrib::make(TransparencyAttrib::M_alpha),
RenderState::get_max_priority());
}
#ifndef NDEBUG
if (m_dual_flash) {
int cycle = (int)(ClockObject::get_global_clock()->get_real_time() * m_dual_flash_rate);
if ((cycle & 1) == 0) {
static CPT(RenderState) flash_state = NULL;
if (flash_state == (const RenderState *)NULL) {
flash_state = state->add_attrib(ColorScaleAttrib::make(LVecBase4f(0.8f, 0.2f, 0.2f, 1.0f)));
}
return flash_state;
}
}
#endif // NDEBUG
return state;
}
////////////////////////////////////////////////////////////////////
// Function: CullResult::get_dual_opaque_state
// Access: Private
// Description: Returns a RenderState that renders only the
// opaque parts of an object, in support of M_dual.
////////////////////////////////////////////////////////////////////
CPT(RenderState) CullResult::
get_dual_opaque_state() {
static CPT(RenderState) state = NULL;
if (state == (const RenderState *)NULL) {
state = RenderState::make(AlphaTestAttrib::make(AlphaTestAttrib::M_greater_equal, dual_opaque_level),
TransparencyAttrib::make(TransparencyAttrib::M_none),
RenderState::get_max_priority());
}
#ifndef NDEBUG
if (m_dual_flash) {
int cycle = (int)(ClockObject::get_global_clock()->get_real_time() * m_dual_flash_rate);
if ((cycle & 1) == 0) {
static CPT(RenderState) flash_state = NULL;
if (flash_state == (const RenderState *)NULL) {
flash_state = state->add_attrib(ColorScaleAttrib::make(LVecBase4f(0.2f, 0.2f, 0.8f, 1.0f)));
}
return flash_state;
}
}
#endif // NDEBUG
return state;
}