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og knuckles

OpenGL issues with binary files to VBO

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so I have been struggling with this problem for a while and have tried many different ways of doing it. Currently I am loading in a binary file that is in bytes and sending it to openGL however nothing is rendering. 

 

this is how I have been creating the binary file

			binaryFloat x,y,z,w,u,v,normx,normy,normz;
			x.f = PD[i].x;
			y.f = PD[i].y;
			z.f = PD[i].z;
			w.f = PD[i].w;
			u.f = PD[i]._U;
			v.f = PD[i]._V;
			normx.f = PD[i].norm.X;
			normy.f = PD[i].norm.Y;
			normz.f = PD[i].norm.Z;

			fout << x.container[0] << x.container[1] << x.container[2] << x.container[3]
				<< y.container[0] << y.container[1] << y.container[2] << y.container[3]
				<< z.container[0] << z.container[1] << z.container[2] << z.container[3]
				<< w.container[0] << w.container[1] << w.container[2] << w.container[3]
				<< u.container[0] << u.container[1] << u.container[2] << u.container[3]
				<< v.container[0] << v.container[1] << v.container[2] << v.container[3]
				<< normx.container[0] << normx.container[1] << normx.container[2] << normx.container[3]
				<< normy.container[0] << normy.container[1] << normy.container[2] << normy.container[3]
				<< normz.container[0] << normz.container[1] << normz.container[2] << normz.container[3];

binaryFloat is a union containing a float and a char[sizeof(float)]. PD is a packedData vector that contains preparsed data.

 

Here is where I load it up in my engine:

	std::ifstream objFile(filename, std::ios::binary);

	if (objFile.is_open())
	{
		unsigned int length;
		char  *data;
		objFile.seekg(0, std::ios::end);
		length = objFile.tellg();
		data = new char[length];
		objFile.seekg(0, std::ios::beg);
		objFile.read(data, length);
		objFile.close();
		e->m_BufferSize = (length / (sizeof(float) * 9));
		glGenVertexArrays(1, &e->m_VAO);
		glBindVertexArray(e->m_VAO);
		glGenBuffers(1, &e->m_Buffer);
		glBindBuffer(GL_ARRAY_BUFFER,  e->m_Buffer);
		glBufferData(GL_ARRAY_BUFFER, length, data, GL_STATIC_DRAW);
		glEnableVertexAttribArray(0);
		glEnableVertexAttribArray(1);
		glEnableVertexAttribArray(2);
		glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, sizeof(float) * 9, BUFFER_OFFSET(0));
		glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(float) * 9, BUFFER_OFFSET(sizeof(float) * 4));
		glVertexAttribPointer(2, 3, GL_FLOAT, GL_FALSE, sizeof(float) * 9, BUFFER_OFFSET(sizeof(float) * 6));
		glBindVertexArray(NULL);
	}

in this snippet I am loading in the file and sending it to openGL and setting the vbo settings in the VAO. When I run this code data does contain the file so I am not sure why its not rendering.

 

Thanks for your help and insight in advance:).

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When you examine in a hex editor the file you created on disk, is the data correct?

 

Did the vertex data get loaded correctly upon examination after the ifstream::read() function returns?

 

Does glGetError() give any errors?

 

Do you correctly render geometry that did not come from a file? (I assume so, since you specifically point out an issue with rendering from content from a file)

 

What does your rendering code look like?

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When you examine in a hex editor the file you created on disk, is the data correct?

 

Did the vertex data get loaded correctly upon examination after the ifstream::read() function returns?

 

Does glGetError() give any errors?

 

Do you correctly render geometry that did not come from a file? (I assume so, since you specifically point out an issue with rendering from content from a file)

 

What does your rendering code look like?

I took the char * data and wrote it to a file and compared the 2 files and they are identical, so I believe that its reading in correctly.

 

glGetError() returns 0 after every vbo and vao GL call.

 

I have rendered stuff to the screen so I know my pipeline is somewhat correct.

 

my render code is :

void renderManager::render() 
{
	SHADER_MANAGER->sendToShader("frustrum", CAMERA->perspectiveMatrix);
	SHADER_MANAGER->sendToShader("view", CAMERA->viewMatrix);
	for (unsigned int i = 0; i < renderingBuffer.size(); i++) 
	{
		SHADER_MANAGER->sendToShader("model", renderingBuffer[i]->PositionMatrix);
		glBindVertexArray(renderingBuffer[i]->m_VAO);
		glDrawArrays(GL_TRIANGLES, 0, renderingBuffer[i]->m_BufferSize);
	}

	glBindVertexArray(NULL);
}

my shaders and program are linked and binded already. In this snippet I am passing my view, projection and model matrix to the shader. 

 

After that I am binding the objects VAO then calling draw.

 

then unbinding all VAOs.

 

as for the hex editor would you be able to recommend one I have notePad++ but im not sure if it has a hex editor plugin

 

thanks for your time

 

 

**so I found the hex editor plugin for notePad++ however I selected the file and ran it and it outputted bad allocation.. 

originally the data was in floats and I put them into a union with a float and a char[4] its a little odd that its corrupted:/

here is a file that im trying to render it is just a small cube that is triangulated 

ÉÞMÁÉÞMÁÉÞMA  €?  À>              €?ÉÞMAÉÞMÁÉÞMA  €?   ?              €?ÉÞMÁÉÞMAÉÞMA  €?  À>  €>          €?ÉÞMÁÉÞMAÉÞMA  €?  À>  €>          €?ÉÞMAÉÞMÁÉÞMA  €?   ?              €?ÉÞMAÉÞMAÉÞMA  €?   ?  €>          €?ÉÞMÁÉÞMAÉÞMA  €?  À>  €>      €?    ÉÞMAÉÞMAÉÞMA  €?   ?  €>      €?    ÉÞMÁÉÞMAÉÞMÁ  €?  À>   ?      €?    ÉÞMÁÉÞMAÉÞMÁ  €?  À>   ?      €?    ÉÞMAÉÞMAÉÞMA  €?   ?  €>      €?    ÉÞMAÉÞMAÉÞMÁ  €?   ?   ?      €?    ÉÞMÁÉÞMAÉÞMÁ  €?  À>   ?          €¿ÉÞMAÉÞMAÉÞMÁ  €?   ?   ?          €¿ÉÞMÁÉÞMÁÉÞMÁ  €?  À>  @?          €¿ÉÞMÁÉÞMÁÉÞMÁ  €?  À>  @?          €¿ÉÞMAÉÞMAÉÞMÁ  €?   ?   ?          €¿ÉÞMAÉÞMÁÉÞMÁ  €?   ?  @?          €¿ÉÞMÁÉÞMÁÉÞMÁ  €?  À>  @?      €¿    ÉÞMAÉÞMÁÉÞMÁ  €?   ?  @?      €¿    ÉÞMÁÉÞMÁÉÞMA  €?  À>  €?      €¿    ÉÞMÁÉÞMÁÉÞMA  €?  À>  €?      €¿    ÉÞMAÉÞMÁÉÞMÁ  €?   ?  @?      €¿    ÉÞMAÉÞMÁÉÞMA  €?   ?  €?      €¿    ÉÞMAÉÞMÁÉÞMA  €?   ?      €?        ÉÞMAÉÞMÁÉÞMÁ  €?  `?      €?        ÉÞMAÉÞMAÉÞMA  €?   ?  €>  €?        ÉÞMAÉÞMAÉÞMA  €?   ?  €>  €?        ÉÞMAÉÞMÁÉÞMÁ  €?  `?      €?        ÉÞMAÉÞMAÉÞMÁ  €?  `?  €>  €?        ÉÞMÁÉÞMÁÉÞMÁ  €?   >      €¿        ÉÞMÁÉÞMÁÉÞMA  €?  À>      €¿        ÉÞMÁÉÞMAÉÞMÁ  €?   >  €>  €¿        ÉÞMÁÉÞMAÉÞMÁ  €?   >  €>  €¿        ÉÞMÁÉÞMÁÉÞMA  €?  À>      €¿        ÉÞMÁÉÞMAÉÞMA  €?  À>  €>  €¿ 
Edited by og knuckles

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so I wrote a little code on the engine to cast it back to float and the data looks perfect:/

heres the code

	for (int i = 0; i < buffer.size() - 3; i += 4) 
		{
	char tempArray[4] = { buffer[i], buffer[i + 1], buffer[i + 2], buffer[i + 3] };
			float f;
			memcpy(&f, &tempArray, sizeof(f));
			packedData.push_back(f);
		}

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Assuming the data and buffers are correct, have you checked the active shader is setup correct?

 

The shaders are correct they have a built in error checking system. :/maybe its my drawing I really am at a loss right now.

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guys I am such an idiot. I wrote some quick camera class and hacked the view matrix real quick to make it do what I want and I changed a scale value that when multiplied by a translation matrix makes the w or data[15] go right out of wack-.-. I am sorry for wasting peoples time. on the plus note I am not crazy lol I went through so much data and everything was working perfectly.

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