First generated node contain unknown information in it's attribute ?

[Seila]

hi,

I try to implement a simple node that expects an input connection with maya's file texture node. Since the input attribute has no connection at the time of node generation i think the input attribute(i.e. "plugin_Texture" in the code snippet) should be NULL. What confusing me is even i set "plugin_Texture" as NULL in constructor, it seems filled in with something before frameBegin call such that I can pass all the condition check even there's not any connection to the "bitmap" attribute of my node. Why settings in constructor not take effect ? And what's filled in "plugin_Texture" parameter ?

What i want to achieve in frameBegin is before retrieving any related interface (or something else) i can make sure that there exist an effective connection to that attriubte\parameter, how to i fix my code to fit this requirement ?

#include "vrayplugins.h"
#include "vrayinterface.h"
#include "vrayrenderer.h"
#include "vraytexutils.h"
#include "defparams.h"

// Prevent from "to tchar*" conversion warning ...
#if (defined __GNUC__) && !(defined __clang__)
	#pragma GCC diagnostic ignored "-Wwrite-strings"
#endif //(defined __GNUC__) && !(defined __clang__)

#include "globalnewdelete.cpp"

using namespace VR;

// Parameters
struct TexSteepParallaxMap_Params: VRayParameterListDesc {
    TexSteepParallaxMap_Params(void) {
        // Add the parameters
	addParamTexture("bitmap", AColor(1.0f, 0.0f, 0.0f, 1.0f), -1, "The input of bitmap texture");
    }
};

struct TexSteepParallaxMap: VRayTexture {
    TexSteepParallaxMap(VRayPluginDesc *pluginDesc) : VRayTexture(pluginDesc) {
	// Set parameter caches
	paramList->setParamCache("bitmap", &plugin_Texture);
	plugin_Texture = NULL;
    }

    void frameBegin(VR::VRayRenderer* vray);
    void frameEnd(VR::VRayRenderer* vray);

    // VRayTexture member function
    AColor getTexColor(const VRayContext &rc);
    void getTexColorBounds(AColor &cmin, AColor &cmax);
    Vector getColorBumpGradient(const VRayContext &rc);

    private:
        PluginBase* plugin_Texture;
};

#define TexSteepParallaxMap_PluginID PluginID(LARGE_CONST(2004110919))
SIMPLE_PLUGIN_LIBRARY(TexSteepParallaxMap_PluginID, EXT_TEXTURE, "TexSteepParallaxMap", "SteepParallaxMap texture plugin for VRay", TexSteepParallaxMap, TexSteepParallaxMap_Params);

void TexSteepParallaxMap::frameBegin(VR::VRayRenderer *vray) {
    // Call the base class to update the parameter caches
    VRayTexture::frameBegin(vray);

    printf("Frame begin called ...\n");

    if(plugin_Texture)
    {
        printf("Get valid texture plugin ...\n");
        
        TextureInterface* texture_interface = (TextureInterface*)GET_INTERFACE(plugin_Texture, EXT_TEXTURE); 
        
        if(texture_interface)
        {
            printf("Get valid texture interface ...\n");
        
            const tchar* n = texture_interface->getInterfaceName();    // <----- Maya crash if i uncomment this line !!!!!!!!!!!!
            //printf("IF name = %s\n", n);
        }
    }
}

void TexSteepParallaxMap::frameEnd(VRayRenderer *vray) {
	VRayTexture::frameEnd(vray);
}


AColor TexSteepParallaxMap::getTexColor(const VRayContext &rc) {

    return AColor(0.0f, 0.0f, 0.0f, 1.0f);
}

void TexSteepParallaxMap::getTexColorBounds(AColor &cmin, AColor &cmax) {
    cmin = AColor(0.0f, 0.0f, 0.0f, 1.0f);
    cmax = AColor(1.0f, 1.0f, 1.0f, 1.0f);
}

Vector TexSteepParallaxMap::getColorBumpGradient(const VRayContext &rc) {
    return Vector(0.0f, 0.0f, 0.0f);
}

[ivaylo.ivanov]

You are using a variant of addParamTexture which has a default value, so it gets assigned to "plugin_Texture" if no parameter is set. If you don't wan't this behaviour, don't pass a default value.

[Seila]

I use the another addParamTexture function with no default value provided but the "plugin_Texture" variable is still not NULL (I've assigned it as NULL in constructor), is this a bug ?

[ivaylo.ivanov]

It seems to work fine on my side.

[Seila]

Could you help me to check what's wrong with my code ? The parameter is still not NULL at first (i.e. i always get red output no matter there is any texture connect to it). Thanks.

#include "vrayplugins.h"
#include "vrayinterface.h"
#include "vrayrenderer.h"
#include "vraytexutils.h"

#include "meshinfobase.h"
#include "meshinfointerface.h"

#include "globalnewdelete.cpp"

#if (defined __GNUC__) && !(defined __clang__)
	#pragma GCC diagnostic ignored "-Wwrite-strings"
#endif //(defined __GNUC__) && !(defined __clang__)

using namespace VR;

// Parameters
struct TexInputTypeTest_Params: VRayParameterListDesc {
    TexInputTypeTest_Params(void) {
        addParamTexture("texture_color");
    }
};

struct TexInputTypeTest: VRayTexture {
    TexInputTypeTest(VRayPluginDesc *pluginDesc):VRayTexture(pluginDesc) {
        // Set parameter caches
		paramList->setParamCache("texture_color", &texture_color);
		
        texture_color = NULL;
    }

	void frameBegin(VR::VRayRenderer *vray) {
	    VRayTexture::frameBegin(vray);

        if(texture_color == NULL)
            testNull = AColor(0.0f, 1.0f, 0.0f, 1.0f);
        else
            testNull = AColor(1.0f, 0.0f, 0.0f, 1.0f);
	}

    AColor getTexColor(const VRayContext &rc);
	void getTexColorBounds(AColor &cmin, AColor &cmax);
	Vector getColorBumpGradient(const VRayContext &rc);
    
    virtual PluginInterface* newInterface(InterfaceID id) { return VRayTexture::newInterface(id); }
    
    // VRayTexture Member function
    PluginBase* getPlugin(void) { return static_cast<PluginBase*>(this); }
    
    // These pure virtual functions have to be implemented if support RTTexInterface
    //int getDataSize(void) { return 0; }
    //void getData(float *fdata) { }
    //int getSource(const char *part,const char *outParam,const char *lang,VUtils::ShaderSource &, OCLData &mtlData);
        
    private:
		TextureInterface* texture_color;
        AColor testNull;
};

#define TexInputTypeTest_PluginID PluginID(LARGE_CONST(2004711829))
SIMPLE_PLUGIN_LIBRARY(TexInputTypeTest_PluginID, EXT_TEXTURE, "TexInputTypeTest", "Test curious input type of VRay plugin", TexInputTypeTest, TexInputTypeTest_Params);


AColor TexInputTypeTest::getTexColor(const VRayContext &rc) {
    return testNull;
}

void TexInputTypeTest::getTexColorBounds(AColor &cmin, AColor &cmax) {
    cmin = AColor(0.0f, 0.0f, 0.0f, 1.0f);
    cmax = AColor(1.0f, 1.0f, 1.0f, 1.0f);
}

Vector TexInputTypeTest::getColorBumpGradient(const VRayContext &rc) {
    return Vector(0.0f, 0.0f, 0.0f);
}

[ivaylo.ivanov]

I don't think there is something wrong with the code. If you have exported the parameter, even if it's holding just a color, it will support the TextureInterface and act like a texture. TextureInterface doesn't provide a method to detect if it holds a simple color, or a real texture. The only way is to have 2 parameters - one for simple color and one for a texture. And if there is no texture, don't export it. I don't think you can do this with desc.txt though, since it's uncommon to need such information. You will need again post translate Python script.

[vlado]

Another way to detect if you have a texture or a flat color is to use the getTexColorBounds() method of the texture. If both the min and max are the same, the input is likely a solid color.

Something like this:

int isTexure=false;
if (texture_color!=NULL) {
    // Figure out if we actually have a texture or just a solid color
    AColor cmin(0.0f, 0.0f, 0.0f, 0.0f);
    AColor cmax(1.0f, 1.0f, 1.0f, 1.0f);
    texture_color->getTexColorBounds(cmin, cmax);
    if (cmin!=cmax) isTexture=true;
}

Best regards,
Vlado

[Seila]

hi vlado,

I encounter similar problem when trying to retrieve PluginBase pointer instead of TextureInterface pointer from parameters. I do something as following but this time the "plugin" pointer is always NULL no matter whether there's Maya's 2d Texture connect to this parameter or not. After checking the .vrscene file i found the connection is totally unrecognized. Since the corresponding Vray plugins for Maya 2d texture nodes are all classified with EXT_TEXTURE I think the following code should work. What's wrong with it ?

I also try to use " GET_INTERFACE(plugin, EXT_TEXTURE)" to get the related interface of the plugin. What really curious is if i use the pointer of TextureInterface as condition the result shows the pointer is also always NULL. This really make me very confusing. Could you provide more detail about this issue ? Thanks.

// Parameters
struct TexInputTypeTest_Params: VRayParameterListDesc {
    TexInputTypeTest_Params(void) {
        addParamPlugin("Plug_Test", EXT_TEXTURE);
    }
};

struct TexInputTypeTest: VRayTexture {
    TexInputTypeTest(VRayPluginDesc *pluginDesc):VRayTexture(pluginDesc) {
        // Set parameter caches
	paramList->setParamCache("Plug_Test", &plugin);
    }

    void frameBegin(VR::VRayRenderer *vray) {
        VRayTexture::frameBegin(vray);

        if(plugin == NULL)
            testNull = AColor(1.0f, 0.0f, 0.0f, 1.0f);
        else
            testNull = AColor(0.0f, 1.0f, 0.0f, 1.0f);
	}
    }

    ...

    private:
        PluginBase* plugin;
    
    ....
}

[vlado]

You need to add the parameter with addParamTexture() and not with addParamPlugin().

Best regards,
Vlado