Irrlicht Engine

Posted: **Tue Jun 15, 2010 5:35 pm**

I've an problem to set more than 4 texture layers. Look what i've done:

1 - Unzip Official Irrlicht 1.7.1 package
2 - Change irrCompileConfig.h to support 8 layers:

Code: Select all

#define _IRR_MATERIAL_MAX_TEXTURES_ 8

3 - run "make" in console.

when i try to set the fourth layer (using GLSL) the mesh is rendered with no texture (just black).

here's my code:

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#include <irrlicht.h>

using namespace irr;
using namespace core;
using namespace scene;
using namespace video;
using namespace io;
using namespace gui;

class MyShaderCallBack : public video::IShaderConstantSetCallBack
{
public:

	virtual void OnSetConstants(video::IMaterialRendererServices* services,
			s32 userData)
	{
	    int d[]	= {0, 1, 2, 3, 4};		//Sampler2d IDs
	    services->setPixelShaderConstant("myTexture",(float*)&d[4],1);
	}
};

int main(int argc, char** argv)
{
    IrrlichtDevice *device = createDevice(EDT_OPENGL, dimension2d<u32>(640, 480), 16, false, false, false, 0);

    IVideoDriver* driver = device->getVideoDriver();
    ISceneManager* smgr = device->getSceneManager();
    IGUIEnvironment* guienv = device->getGUIEnvironment();

    ISceneNode* node = smgr->addCubeSceneNode(10);

    MyShaderCallBack* mc = new MyShaderCallBack();

    static s32 material=smgr->getVideoDriver()->getGPUProgrammingServices()->addHighLevelShaderMaterialFromFiles(
        "shader.vert", "vertexMain", video::EVST_VS_3_0,
        "shader.frag", "pixelMain", video::EPST_PS_3_0,
        mc, video::EMT_SOLID);

    node->setMaterialTexture(0,driver->getTexture("L0.png"));
    node->setMaterialTexture(1,driver->getTexture("L1.jpg"));
    node->setMaterialTexture(2,driver->getTexture("L2.jpg"));
    node->setMaterialTexture(3,driver->getTexture("L3.jpg"));
    node->setMaterialTexture(4,driver->getTexture("L4.jpg"));

    node->setMaterialFlag(EMF_LIGHTING,false);
    node->setMaterialType((E_MATERIAL_TYPE)material);

    smgr->addCameraSceneNode(0, vector3df(0,30,-40), vector3df(0,5,0));

    while(device->run())
    {
        driver->beginScene(true, true, SColor(0,200,200,200));

        smgr->drawAll();
        guienv->drawAll();

        driver->endScene();
    }
    device->drop();

    return 0;
}

GLSL vertex program:

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void main(void)
{
	gl_Position = ftransform();
	gl_TexCoord[0] = gl_MultiTexCoord0;
}

GLSL fragment program:

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uniform sampler2D myTexture;

void main (void)
{
    gl_FragColor = texture2D(myTexture, vec2(gl_TexCoord[0]));
}

Why does not work? there is anything else i need to do before compile irrlicht?

PS: OpenSUSE 11.2 + OpenGL 3.2.0 + GLSL 1.5 on Nvidia 9500M GS.

Posted: **Tue Jun 15, 2010 11:43 pm**

This seems have, easy solution.

You have compiled well the Irrlicht and the problem is in the code and the programming of the GLSL.

You can do this the way I was doing, or do it this way, but always stating the textures in the GLSL.

In the code needed something like this:

Code: Select all

class MyShaderCallBack : public video::IShaderConstantSetCallBack
{
public:

   virtual void OnSetConstants(video::IMaterialRendererServices* services,
         s32 userData)
   {
       int d[]   = {0, 1, 2, 3, 4};      //Sampler2d IDs
       services->setPixelShaderConstant("myTexture0",(float*)&d[0],1);
       services->setPixelShaderConstant("myTexture1",(float*)&d[1],1);
       services->setPixelShaderConstant("myTexture2",(float*)&d[2],1);
       services->setPixelShaderConstant("myTexture3",(float*)&d[3],1);
       services->setPixelShaderConstant("myTexture4",(float*)&d[4],1);
   }
};

And in the GLSL program:

Code: Select all

uniform sampler2D myTexture0;
uniform sampler2D myTexture1;
uniform sampler2D myTexture2;
uniform sampler2D myTexture3;
uniform sampler2D myTexture4;

void main (void)
{
//Here, we must modify the code to do what you want, multi texture, adder ...

..
..
..
    gl_FragColor = texture2D(myTexture0, vec2(gl_TexCoord[0]));
}

I hope that this will be of assistance

Posted: **Wed Jun 16, 2010 1:17 am**

don't work.

apparently the OpenGL driver does not recognize my graphics card texture units limit.

In COpenGLExtensionHandler.h the driver try to get MaxTextureUnits, but in my case result apparent to be 4 (Wrong cause Geforce 9500 has 16 Texture Units). So i've changed the line:

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MaxTextureUnits=static_cast<u8>(num);

setting manually to 8 :

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MaxTextureUnits=8;

I now this is not a good solution, but i think it can be a bug (correct me if i'm wrong) and need to be resolved in irrlicht.

Posted: **Wed Jun 16, 2010 2:21 am**

Interesting, nice find. Unfortunately since it's on Linux it's most likely just a driver bug, I'll have to test it under windows and see.

Moving to Bug Reports.

Posted: **Wed Jun 16, 2010 8:00 am**

I use something like this:

Code: Select all

diff -rupN irrlicht-1.7.1/source/Irrlicht/COpenGLExtensionHandler.cpp irrlicht-1.7.1_patch3/source/Irrlicht/COpenGLExtensionHandler.cpp
--- irrlicht-1.7.1/source/Irrlicht/COpenGLExtensionHandler.cpp  2010-02-14 13:04:58.000000000 +0100
+++ irrlicht-1.7.1_patch3/source/Irrlicht/COpenGLExtensionHandler.cpp 2010-06-11 09:41:42.000000000 +0200
@@ -467,6 +467,9 @@ void COpenGLExtensionHandler::initExtens
    {
        glGetIntegerv(GL_MAX_TEXTURE_UNITS, &num);
        MaxTextureUnits=static_cast<u8>(num);
+        glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS_ARB, &num);
+        if (MaxTextureUnits<static_cast<u8>(num))
+            MaxTextureUnits=static_cast<u8>(num);
    }
 #endif
    glGetIntegerv(GL_MAX_LIGHTS, &num);

Posted: **Wed Jun 16, 2010 5:40 pm**

bmwop wrote:I use something like this:

Code: Select all

diff -rupN irrlicht-1.7.1/source/Irrlicht/COpenGLExtensionHandler.cpp irrlicht-1.7.1_patch3/source/Irrlicht/COpenGLExtensionHandler.cpp
--- irrlicht-1.7.1/source/Irrlicht/COpenGLExtensionHandler.cpp  2010-02-14 13:04:58.000000000 +0100
+++ irrlicht-1.7.1_patch3/source/Irrlicht/COpenGLExtensionHandler.cpp 2010-06-11 09:41:42.000000000 +0200
@@ -467,6 +467,9 @@ void COpenGLExtensionHandler::initExtens
    {
        glGetIntegerv(GL_MAX_TEXTURE_UNITS, &num);
        MaxTextureUnits=static_cast<u8>(num);
+        glGetIntegerv(GL_MAX_TEXTURE_IMAGE_UNITS_ARB, &num);
+        if (MaxTextureUnits<static_cast<u8>(num))
+            MaxTextureUnits=static_cast<u8>(num);
    }
 #endif
    glGetIntegerv(GL_MAX_LIGHTS, &num);

Thanks, works fine.

Posted: **Wed Jun 16, 2010 8:54 pm**

Everything is ok, Irrlicht use GL_MAX_TEXTURE_UNITS as texture limit in OpenGL. On modern cards GL_MAX_TEXTURE_UNITS is equal 4 or 8. This number is important only for fixed function (glEnable/glDisable, glTexEnv, glGetTexEnv etc.) for programmable pipeline, so OpenGL 2.0+ You should use GL_MAX_TEXTURE_IMAGE_UNITS (for max avaiable textures in fragment shader), GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS (for vertex shader) and GL_MAX_GEOMETRY_TEXTURE_IMAGE_UNITS (for geometry shader in OGL3.2).

Posted: **Mon Aug 02, 2010 11:32 am**

I founded a problem same you on Geforce 9600 GS (update with lastest driver). Try set _IRR_MATERIAL_MAX_TEXTURES_ is 8 but opengl driver return 4 (used GL_MAX_TEXTURE_UNITS). When i change to GL_MAX_TEXTURE_IMAGE_UNITS_ARB my program will work correctly. This's good to change GL_MAX_TEXTURE_UNITS to GL_MAX_TEXTURE_IMAGE_UNITS_ARB or not ? Please suggestion me...
best regards,

Posted: **Mon Aug 02, 2010 1:25 pm**

i think this is answer:
http://developer.nvidia.com/object/General_FAQ.html#t6

Posted: **Mon Aug 02, 2010 2:49 pm**

Thanks, It's clear.

Posted: **Mon Aug 02, 2010 4:34 pm**

Thanks for the link. This will definitely help to improve the current texture handling in Irrlicht.

Irrlicht Engine

Problem with more than 4 texture layers - Irrlicht 1.7.1

Problem with more than 4 texture layers - Irrlicht 1.7.1