GLbyte

GLBYTE refers to the 8-bit signed integer data type used in the OpenGL graphics API. In OpenGL’s C bindings, the corresponding type is GLbyte, a typedef for signed char, while GL_BYTE is the enumerant used to specify this data type in API calls. GLbyte is typically applied to vertex attribute data, colors, and other fixed‑point buffers that require compact numeric representations.

Technical details include the 8-bit width and the value range from -128 to 127. When OpenGL functions receive data of type GL_BYTE (for example via glVertexAttribPointer or related color pointers), the interpretation of the values depends on the normalization parameter. If normalization is enabled (normalized = GL_TRUE), the data are mapped to the standard range [-1, 1], with -128 mapping to -1.0 and 127 mapping to 1.0. If normalization is disabled (normalized = GL_FALSE), the values are converted to floating-point in a way determined by the type’s integer range, with the exact scaling depending on the driver implementation.

Usage in practice varies: GL_BYTE is often less common for color data, where GL_UNSIGNED_BYTE is preferred to represent 0–255. It is more frequently used for other signed vertex attributes or buffer data where a small, signed range is appropriate. Modern OpenGL profiles still support GL_BYTE as a valid attribute data type, but developers may choose alternative types (such as GL_SHORT or GL_FLOAT) depending on precision and performance needs.

GLBYTE/GLbyte is part of the broader family of OpenGL types defined by the Khronos Group, alongside other signed and unsigned integers and floating-point types. It remains a fundamental primitive for low‑level buffer data in OpenGL, particularly when compact signed integer representation is required.

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