Irrlicht Engine

Irrlicht clears the shader memory only if the irrlicht device is deleted (Irrlicht device is created using CreateDevice(..) method ). This caused a huge memory leak in my project, in which multiple number of unique shaders are needed to be generated and removed without deleting the irrlicht device frequently. For removing the memory of the shader materials which is not necessary at some point of time i’ve written removeShaderMaterials() method.

Add the lines which starts with + symbol

Changes in Irrlicht Classes:

Class: IVideoDriver.h
Line: Anywhere under public category
Change:
class IVideoDriver : public virtual IReferenceCounted
{
public:
+ virtual void removeShaderProgram(int materialIndex)= 0;


Class: CNullDriver.h
Line: Anywhere under public category
Change:
class CNullDriver : public IVideoDriver, public IGPUProgrammingServices
{
public:
+virtual void removeShaderMaterials();

Class: CNullDriver.cpp
Line: Anywhere under public category
Change:
+void CNullDriver::emoveShaderMaterials() {
+}

Class: COGLES2Driver.h
Line: Anywhere under public category
Change:
+virtual void removeShaderMaterials();
+core array<GLuint> *shaderMaterials;


Class: COGLES2Driver.cpp
Change1:
core::dimension2d<u32> WindowSize(backingWidth, backingHeight);
CNullDriver::ScreenSize = WindowSize;
CNullDriver::ViewPort = core::rect<s32>(core::position2d<s32>(0,0), core::dimension2di(WindowSize));

genericDriverInit(WindowSize, params.Stencilbuffer);
+ shaderPrograms = new core::array<GLuint>();
materialRenderers = new irr::core::array<irr::video::COGLES2MaterialRenderer*>();
#endif
}
Change2:
+void COGLES2Driver::removeShaderMaterials(){

+ for(int i = 0;i < shaderMaterials->size();i++){
+ GLuint Program = (* shaderMaterials);
+ if (Program)
+ {
+ GLuint shaders[8];
+ GLint count;
+ glGetAttachedShaders(Program, 8, &count, shaders);
+
+ count=core::min_(count,8);
+ for (GLint i=0; i<count; ++i)
+ glDeleteShader(shaders);
+ glDeleteProgram(Program);
+ Program = 0;
+ }
+ (*materialRenderers)->UniformInfo.clear();
+ }
+ }
+}

Change3:
s32 COGLES2Driver::addHighLevelShaderMaterial(
const c8* vertexShaderProgram,
const c8* vertexShaderEntryPointName,
E_VERTEX_SHADER_TYPE vsCompileTarget,
const c8* pixelShaderProgram,
const c8* pixelShaderEntryPointName,
E_PIXEL_SHADER_TYPE psCompileTarget,
const c8* geometryShaderProgram,
const c8* geometryShaderEntryPointName,
E_GEOMETRY_SHADER_TYPE gsCompileTarget,
scene::E_PRIMITIVE_TYPE inType,
scene::E_PRIMITIVE_TYPE outType,
u32 verticesOut,
IShaderConstantSetCallBack* callback,
E_MATERIAL_TYPE baseMaterial,
s32 userData, E_GPU_SHADING_LANGUAGE shadingLang)
{
s32 nr = -1;
COGLES2MaterialRenderer* r = new COGLES2MaterialRenderer(this, nr, vertexShaderProgram,pixelShaderProgram,callback, baseMaterial, userData);
+ shaderPrograms->push_back(r->getProgram());
materialRenderers->push_back(r);
r->drop();
return nr;
}
Change4:
//! destructor
COGLES2Driver::~COGLES2Driver()
{
+ delete shaderPrograms;
delete materialRenderers;

Change5:
Class: COGLES2MaterialRenderer.cpp

GLuint COGLES2MaterialRenderer::getProgram() const
{
return Program;
}

while rewriting for OGL 3.2 core compliance in shaders, I noticed how shaders are bound to material IDs.... you could make a "bool removeShader(video::E_MATERIAL_TYPE)" method to remove shader by its ID

yes you are right, we can edit these methods depending on our convenience.