void MultiDrawIndirect::SetupMultiDrawParameters()
{
unsigned int j;
NvModel* pData;
unsigned int VertexOffset;
unsigned int IndexOffset;
glBindBuffer(GL_DRAW_INDIRECT_BUFFER, m_IndirectDrawBuffer);
CHECK_GL_ERROR();
VertexOffset = 0;
IndexOffset = 0;
CHECK_GL_ERROR();
pData = m_Model->getModel();
for (j = 0; j < m_GridSize * m_GridSize; j++)
{
VertexOffset = (j % MAX_MODEL_INSTANCES) * pData->getCompiledVertexCount();
m_MultidrawCommands[j].count = pData->getCompiledIndexCount(NvModelPrimType::TRIANGLES);
m_MultidrawCommands[j].instanceCount = 1;
m_MultidrawCommands[j].firstIndex = IndexOffset;
m_MultidrawCommands[j].baseVertex = VertexOffset;
m_MultidrawCommands[j].baseInstance = j;
}
IndexOffset += pData->getCompiledIndexCount();
glBindBuffer(GL_DRAW_INDIRECT_BUFFER, 0);
CHECK_GL_ERROR();
}
void MultiDrawIndirect::DrawAsSingleCalls()
{
unsigned int j;
NvModel* pData;
unsigned int VertexOffset;
unsigned int IndexOffset;
VertexOffset = 0;
IndexOffset = 0;
glBindVertexArray(m_VertexArrayObject);
pData = m_Model->getModel();
for (j = 0; j < m_GridSize * m_GridSize; j++)
{
VertexOffset = (j % MAX_MODEL_INSTANCES) * pData->getCompiledVertexCount();
glUniform2f(m_SceneShader->m_PositionUHandle, m_Offsets[2 * j], m_Offsets[(2 * j) + 1]);
glDrawElementsBaseVertex( GL_TRIANGLES,
pData->getCompiledIndexCount(NvModelPrimType::TRIANGLES),
GL_UNSIGNED_INT,
(GLvoid *) (IndexOffset * sizeof(IndexOffset)),
VertexOffset);
}
IndexOffset += pData->getCompiledIndexCount();
glBindVertexArray(0);
CHECK_GL_ERROR();
}
void MultiDrawIndirect::SetConstants()
{
std::vector<NvGLModel*>::iterator ii;
NvModel* pData;
int32_t SizeOfCompiledVertex;
unsigned int NumberOfCompiledVertices;
unsigned int NumberOfIndices;
pData = m_Model->getModel();
NumberOfCompiledVertices = 0;
NumberOfIndices = 0;
SizeOfCompiledVertex = pData->getCompiledVertexSize();
NumberOfCompiledVertices += pData->getCompiledVertexCount();
NumberOfIndices += pData->getCompiledIndexCount(NvModelPrimType::TRIANGLES);
m_IndexSize = sizeof(uint32_t);
m_VertexSize = sizeof(float) * SizeOfCompiledVertex;
m_SizeofIndexBuffer = NumberOfIndices * m_IndexSize;
// Vertices
m_SizeofVertexBuffer = NumberOfCompiledVertices * m_VertexSize * m_MaxModelInstances;
m_OffsetofInstanceBuffer = m_SizeofVertexBuffer;
m_SizeofVertexBuffer += 2 * sizeof(GLfloat) * m_MaxGridSize * m_MaxGridSize;
}
void InstancingApp::initGLObjects( int32_t sceneIndex, float* pV, int32_t* pI, NvModelGL* pMdl )
{
NvModelPrimType::Enum prim;
NvModel *pBaseMdl = pMdl->getModel();
int32_t floatCount = pBaseMdl->getCompiledVertexCount() * pBaseMdl->getCompiledVertexSize() * MAX_INSTANCES;
int32_t intCount = pBaseMdl->getCompiledIndexCount(prim) * MAX_INSTANCES;
// create vbo from the data
glGenBuffers(1, &m_vboID[sceneIndex]);
glBindBuffer(GL_ARRAY_BUFFER, m_vboID[sceneIndex]);
glBufferData(GL_ARRAY_BUFFER, floatCount * sizeof(float) + 6 * MAX_OBJECTS * sizeof(float), pV, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
// create ibo from the data
glGenBuffers(1, &m_iboID[sceneIndex]);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, m_iboID[sceneIndex]);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, intCount * sizeof(uint32_t), pI, GL_STATIC_DRAW);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}
bool InstancingApp::initSceneInstancingData( int32_t sceneIndex )
{
NvModelPrimType::Enum prim;
NvModelGL* pMdl = m_pModel[sceneIndex];
NvModel *pBaseMdl = pMdl->getModel();
int32_t floatCount = pBaseMdl->getCompiledVertexCount() * pBaseMdl->getCompiledVertexSize() * MAX_INSTANCES;
int32_t intCount = pBaseMdl->getCompiledIndexCount(prim) * MAX_INSTANCES;
// array big enough to hold n instances and data for hw instancing
// after n copies of the vertex data of the object there is room
// for all position and rotation data for all instances
float* pV = new float[ floatCount + 6 * MAX_OBJECTS ];
GLint* pI = new GLint[ intCount ];
// early out if no data
if( pV == 0 || pI == 0 )
{
if( pV )
delete[] pV;
if( pI )
delete[] pI;
return false;
}
// ptr to the per object instancing data in the vbo
float* phwInstanceData = pV + floatCount;
// init data for this scene
initSceneColorPalette( sceneIndex );
initPerInstanceRotations( sceneIndex, phwInstanceData );
initPerInstancePositions( sceneIndex, phwInstanceData );
initModelCopies( sceneIndex, pV, pI, pMdl );
initGLObjects( sceneIndex, pV, pI, pMdl );
// free temp data
delete[] pV;
delete[] pI;
return true;
}
void InstancingApp::initModelCopies( int32_t sceneIndex, float* pV, int32_t* pI, NvModelGL* pMdl )
{
NvModel *pBaseMdl = pMdl->getModel();
NvModelPrimType::Enum prim;
int32_t vtxSize = pBaseMdl->getCompiledVertexSize();
int32_t vtxCount = pBaseMdl->getCompiledVertexCount();
int32_t idxCount = pBaseMdl->getCompiledIndexCount(prim);
int32_t tcOff = pBaseMdl->getCompiledTexCoordOffset();
const float* pModel = pBaseMdl->getCompiledVertices();
// write MAX_INSTANCES copies of the scene object to be instanced to
// a big vertex buffer and index buffer - this data is used in the
// shader instancing rendering path
for( int32_t i = 0; i < MAX_INSTANCES; ++i )
{
int32_t voff = vtxCount * vtxSize * i;
int32_t ioff = idxCount * i;
for( int32_t v = 0; v < vtxCount; ++v )
{
// copy original vertex
memcpy( (void*) &pV[ voff + v * vtxSize ],
(void*) &pModel[ v * vtxSize ],
vtxSize * sizeof( float) );
// patch instance id into .z component of the 3d texture coordinates
pV[ voff + v * vtxSize + tcOff + 2 ] = float( i );
}
// copy indices and modify them accordingly
for( int32_t idx = 0; idx < idxCount; ++idx )
{
pI[ioff + idx] = *(pBaseMdl->getCompiledIndices(prim) + idx);
pI[ ioff + idx ] += vtxCount * i;
}
}
}
void MultiDrawIndirect::SetupMultipleModelData()
{
NvModel* pData;
float* pVertexData;
uint32_t* pIndexData;
unsigned int j;
pIndexData = (uint32_t *) glMapBufferRange( GL_ELEMENT_ARRAY_BUFFER, 0,
m_SizeofIndexBuffer,
GL_MAP_WRITE_BIT | GL_MAP_INVALIDATE_BUFFER_BIT);
pVertexData = (float *) glMapBufferRange( GL_ARRAY_BUFFER, 0,
m_SizeofVertexBuffer,
GL_MAP_WRITE_BIT | GL_MAP_INVALIDATE_BUFFER_BIT);
pData = m_Model->getModel();
for (unsigned int k = 0; k < m_MaxModelInstances; k++)
{
float *pPositionData, Scale;
memcpy( pVertexData,
pData->getCompiledVertices(),
pData->getCompiledVertexCount() * m_VertexSize);
pPositionData = pVertexData;
Scale = 1.0f + (rand() / (float) RAND_MAX) * 3.0f;;
for (int z = 0; z < pData->getCompiledVertexCount(); z++)
{
pPositionData[0] = pPositionData[0];
pPositionData[1] = pPositionData[1] * Scale;
pPositionData[2] = pPositionData[2];
pPositionData += pData->getCompiledVertexSize();
}
pVertexData += pData->getCompiledVertexCount() * pData->getCompiledVertexSize();
}
memcpy( pIndexData,
pData->getCompiledIndices(NvModelPrimType::TRIANGLES),
pData->getCompiledIndexCount() * m_IndexSize);
pIndexData += pData->getCompiledIndexCount();
float* pInstData = (float*)pVertexData;
for (j = 0; j < m_MaxGridSize; j++)
{
GetGridPoints(j, m_Offsets);
}
for (j = 0; j < m_MaxGridSize * m_MaxGridSize; j++)
{
*(pInstData++) = m_Offsets[2 * j];
*(pInstData++) = m_Offsets[(2 * j) + 1];
}
glUnmapBuffer(GL_ELEMENT_ARRAY_BUFFER);
glUnmapBuffer(GL_ARRAY_BUFFER);
}