Trouble to access attributes by using glVertexArrayAttribFormat / glVertexArrayVertexBuffer [closed] - c++

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I have this code :
Upp::Vector<float> verticesTriangle{
1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, -0.5f, -0.5f, 0.0f,
0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.5f, -0.5f, 0.0f,
0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.0f, 0.5f, 0.0f,
};
glGenVertexArrays(1, &VAO);
glBindVertexArray(VAO);
//Setting up the VAO Attribute format
glVertexArrayAttribFormat(VAO, 0, 3, GL_FLOAT, GL_FALSE, 0); //Will be colors (R G B in float)
glVertexArrayAttribFormat(VAO, 1, 2, GL_FLOAT, GL_FALSE, 3); //Will be texture coordinates
glVertexArrayAttribFormat(VAO, 2, 3, GL_FLOAT, GL_FALSE, 5); //Normals
glVertexArrayAttribFormat(VAO, 3, 3, GL_FLOAT, GL_FALSE, 8); //Will be my position
glEnableVertexArrayAttrib(VAO, 0);
glEnableVertexArrayAttrib(VAO, 1);
glEnableVertexArrayAttrib(VAO, 2);
glEnableVertexArrayAttrib(VAO, 3);
//Generating a VBO
glGenBuffers(1, &VBOCarre);
glBindBuffer(GL_ARRAY_BUFFER, VBOCarre);
glBufferStorage(GL_ARRAY_BUFFER, sizeof(float) * verticesTriangle.GetCount(), verticesTriangle, GL_MAP_READ_BIT | GL_MAP_WRITE_BIT);
//Binding the VBO to be read by VAO
glVertexArrayVertexBuffer(VAO, 0, VBOCarre, 0 * sizeof(float), 11 * sizeof(float));
glVertexArrayVertexBuffer(VAO, 1, VBOCarre, 3 * sizeof(float), 11 * sizeof(float));
glVertexArrayVertexBuffer(VAO, 2, VBOCarre, 5 * sizeof(float), 11 * sizeof(float));
glVertexArrayVertexBuffer(VAO, 3, VBOCarre, 8 * sizeof(float), 11 * sizeof(float));
//Bind VAO
glBindVertexArray(VAO);
I have no problem retrieving the first attribute in my shader however, when I trying to retrieve others, It dont work. To test it, I have setup an float array and a simple shader program and I try to retrieve my position to draw a triangle.
Here is how my datas are ordered :
Here is my vertex shader :
#version 400
layout (location = 0) in vec3 colors;
layout (location = 1) in vec2 textCoords;
layout (location = 2) in vec3 normals;
layout (location = 3) in vec3 positions;
out vec3 fs_colors;
void main()
{
gl_Position = vec4(positions.x, positions.y, positions.z, 1.0);
// gl_Position = vec4(colors.x, colors.y, colors.z, 1.0); //This line work, proofing my
// first attribute is sended well to my shader
fs_colors = colors;
}
The problem is, except the first attribute, all others seems to not be sent to the shader. What am I missing ?!

Answer 1

You're putting stuff in the wrong place.
glVertexArrayAttribFormat(VAO, 1, 2, GL_FLOAT, GL_FALSE, 3); //Will be texture coordinates
The "3" here is being passed as a byte offset from the start of a vertex in the array to the particular data for that vertex in the attribute. Obviously, your texture coordinate is not 3 bytes from the start of your vertex; it's 3 * sizeof(float) bytes from the start of the vertex.
Similarly:
glVertexArrayVertexBuffer(VAO, 1, VBOCarre, 3 * sizeof(float), 11 * sizeof(float));
This makes no sense either. You're only using a single buffer, and all four attributes read from the same binding. So you should only bind a single buffer.
The offset ought to be 0, because that's where a vertex in the buffer starts. And the stride should be what you wrote.
You also never directly set the association between the attributes and the binding index with glVertexArrayAttribBinding. You probably got things to work by relying on the default, but you shouldn't be using the default here.
The correct code would be:
//Generating a VBO
glCreateBuffers(1, &VBOCarre);
//No need to call glBindBuffer(GL_ARRAY_BUFFER, VBOCarre);, since we're doing DSA.
glNamedBufferStorage(VBOCarre, sizeof(float) * verticesTriangle.GetCount(), verticesTriangle, GL_MAP_READ_BIT | GL_MAP_WRITE_BIT);
glCreateVertexArrays(1, &VAO);
//No need to glBindVertexArray(VAO);, since we're using DSA.
//Setting up the VAO Attribute format
glEnableVertexArrayAttrib(VAO, 0);
glVertexArrayAttribFormat(VAO, 0, 3, GL_FLOAT, GL_FALSE, 0); //Will be colors (R G B in float)
glEnableVertexArrayAttrib(VAO, 1);
glVertexArrayAttribFormat(VAO, 1, 2, GL_FLOAT, GL_FALSE, 3 * sizeof(float)); //Will be texture coordinates
glEnableVertexArrayAttrib(VAO, 2);
glVertexArrayAttribFormat(VAO, 2, 3, GL_FLOAT, GL_FALSE, 5 * sizeof(float)); //Normals
glEnableVertexArrayAttrib(VAO, 3);
glVertexArrayAttribFormat(VAO, 3, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(float)); //Will be my position
//One buffer, one binding.
glVertexArrayVertexBuffer(VAO, 0, VBOCarre, 0, 11 * sizeof(float));
//Make all attributes read from the same buffer.
glVertexArrayAttribBinding(VAO, 0, 0);
glVertexArrayAttribBinding(VAO, 1, 0);
glVertexArrayAttribBinding(VAO, 2, 0);
glVertexArrayAttribBinding(VAO, 3, 0);
//We can glBindVertexArray(VAO); when we're about to use it, not just because we finished setting it up.