gl_FragColor and TriangleStrip problem [SOLVED]

OpenGL OpenGL: Basic Coding
1

Hello !
I have started studying OpenGL one week ago and using it with OpenTK NET frameworks.
I have a 7 years experience in programming, 3D data & computing.
My problem is particular, I have found “kind of” similar topics in this forum (2 topics) but either the closing answer was not answering my problem at all, either the problem was too different from mine.
I am using a custom VertexBuffer interpretating data from a byte array for personnal purposes.

GL.BindVertexArray(VertexArrayObject);
GL.BindBuffer(BufferTarget.ArrayBuffer, VertexBufferObject);
GL.BufferData(BufferTarget.ArrayBuffer, this.Data.Length, this.Data, BufferUsageHint.StaticDraw);

GL.VertexAttribPointer(0, 3, VertexAttribPointerType.Float, false, this.VertexStride, 0);
GL.EnableVertexAttribArray(0);

GL.VertexAttribIPointer(1, 1, VertexAttribIntegerType.Int, this.VertexStride, (IntPtr)(3 * sizeof(float)));
GL.EnableVertexAttribArray(1);

The images explain everything. The triangle is not displaying as expected, while the fragColor is set correctly, four times, with the correct colors, at the expected order.
It looks like only the color set at the moment the triangle strip draws a triangle, appears.

I’ve been looking for an anwer for a while now, I’de be really glad if a benevolent mind could help me figure the issue.
Thank you !

image
image1512×1040 68.1 KB


htttp://www.soraiko.ovh/Links/1805202012311.png

1512×1040 68.1 KB

805×399 24.4 KB

2

Problem solved thanks to a friend.
There was a solution keeping using 4 bytes and not 16 (The reason I was using an integer)
I had to pass the data as vec4 and not integer in both the shading and raster steps, and use a four dimensions unsigned byte array instead. The shading program converts them to vec4 when normalised.
GL.VertexAttribPointer(1, 4, VertexAttribPointerType.UnsignedByte, true, this.VertexStride, 3 * sizeof(float));