opengl_vbo_structure

OpenGL vertex buffer (VBO) holding one per-vertex or per-instance array of vec2, vec3 or vec4.

Derives from: opengl_gpu_buffer

1 functions take it 0 return it 0 operators

Fields and methods

Members of the struct opengl_vbo_structure. Most of what you do with a CGP type goes through the free functions listed below.

Fields

GLuint divisor = 0 Instancing divisor given to initialize_data_on_gpu: 0 for per-vertex data, 1 to advance once per instance (applied by opengl_set_vao_location).

Methods

`void initialize_data_on_gpu(numarray<vec3> const& data, GLuint divisor = 0)`	Allocates a new VBO (glBufferData, GL_DYNAMIC_DRAW) holding the vec3 array and stores its id, size and divisor.3 overloads src
`void initialize_data_on_gpu(numarray<vec2> const& data, GLuint divisor = 0)`	Allocates a new VBO (glBufferData, GL_DYNAMIC_DRAW) holding the vec2 array and stores its id, size and divisor. src
`void initialize_data_on_gpu(numarray<vec4> const& data, GLuint divisor = 0)`	Allocates a new VBO (glBufferData, GL_DYNAMIC_DRAW) holding the vec4 array and stores its id, size and divisor. src
	Prints a warning if the VBO was already allocated, whose memory is then lost.
`void update(numarray<vec2> const& data, int size_elements_update = -1)`	Overwrites the start of the VBO with the vec2 array (glBufferSubData, no reallocation), all of it or its first size_elements_update elements, and stops on an assertion if this exceeds the allocated size.3 overloads src
`void update(numarray<vec3> const& data, int size_elements_update = -1)`	Overwrites the start of the VBO with the vec3 array (glBufferSubData, no reallocation), all of it or its first size_elements_update elements, and stops on an assertion if this exceeds the allocated size. src
`void update(numarray<vec4> const& data, int size_elements_update = -1)`	Overwrites the start of the VBO with the vec4 array (glBufferSubData, no reallocation), all of it or its first size_elements_update elements, and stops on an assertion if this exceeds the allocated size. src

Inherited from opengl_gpu_buffer (7 members)

Fields

`GLuint id = 0`	OpenGL id of the buffer, 0 when it is not allocated.
`GLuint size = 0`	Number of elements in the buffer (a vec3 or a uint3 counts as one element), 0 when empty.
`GLenum type = 0`	OpenGL target of the buffer, GL_ARRAY_BUFFER for a VBO and GL_ELEMENT_ARRAY_BUFFER for an EBO.
`opengl_gpu_buffer_details details`	Allocated size in bytes, number of components per element (2, 3 or 4) and component type (GL_FLOAT), used to describe the buffer to the VAO.

Methods

`void bind() const`	Binds the buffer to its target (glBindBuffer) when its id is not 0. src
`void unbind() const`	Unbinds any buffer from the target of this buffer (glBindBuffer with 0). src
`void clear()`	Deletes the buffer on the GPU (glDeleteBuffers) and resets id, size, type and details to 0. src

Functions taking a opengl_vbo_structure

Other 1

opengl_set_vao_location

source

void opengl_set_vao_location(opengl_vbo_structure const& vbo, GLuint location_index)

Bind a VBO to a shader attribute location of the current VAO (glVertexAttribPointer), also setting the instancing divisor if the VBO has one.

Functions returning a opengl_vbo_structure

None.

Operators

None.