private void initBuffers(GL3 gl) {
// IDs for 2 buffers
int[] buffArray = new int[2];
gl.glGenBuffers(buffArray.length, buffArray, 0);
vbo = buffArray[0];
assert vbo > 0;
// Bind buffer and upload data
gl.glBindBuffer(GL3.GL_ARRAY_BUFFER, vbo);
gl.glBufferData(
GL3.GL_ARRAY_BUFFER,
vertexColorData.length * Buffers.SIZEOF_FLOAT,
vertexColorDataBuffer,
GL3.GL_STATIC_DRAW);
gl.glBindBuffer(GL3.GL_ARRAY_BUFFER, 0);
// Buffer with the 3 indices required for one triangle
ibo = buffArray[1];
assert ibo > 0;
gl.glBindBuffer(GL3.GL_ELEMENT_ARRAY_BUFFER, ibo);
gl.glBufferData(
GL3.GL_ELEMENT_ARRAY_BUFFER,
indices.length * Buffers.SIZEOF_SHORT,
indicesBuffer,
GL3.GL_STATIC_DRAW);
gl.glBindBuffer(GL3.GL_ELEMENT_ARRAY_BUFFER, 0);
}
/**
* Constructor that creates a Vertex Buffer Object with the specified GLSL attributes. (typically
* location, texture coordinates, normals, etc.)
*
* @param gl The global openGL instance.
* @param attribs One or more attributes that represent this VBO, @see GLSLAttrib
*/
public VBO(GL3 gl, GLSLAttrib... attribs) {
this.attribs = attribs;
// Generate a new internal OpenGL VBO pointer
this.vboPointer = Buffers.newDirectIntBuffer(1);
gl.glGenVertexArrays(1, this.vboPointer);
gl.glBindVertexArray(this.vboPointer.get(0));
// Generate a new internal OpenGL Array Buffer pointer
this.bufferPointer = Buffers.newDirectIntBuffer(1);
gl.glGenBuffers(1, this.bufferPointer);
gl.glBindBuffer(GL3.GL_ARRAY_BUFFER, this.bufferPointer.get(0));
// Allocate enough memory
int size = 0;
for (final GLSLAttrib attrib : attribs) {
size += attrib.buffer.capacity() * Buffers.SIZEOF_FLOAT;
}
gl.glBufferData(GL3.GL_ARRAY_BUFFER, size, (Buffer) null, GL3.GL_STATIC_DRAW);
// Copy the GLSL Attribute data into the internal OpenGL buffer
int nextStart = 0;
for (final GLSLAttrib attrib : attribs) {
gl.glBufferSubData(
GL3.GL_ARRAY_BUFFER,
nextStart,
attrib.buffer.capacity() * Buffers.SIZEOF_FLOAT,
attrib.buffer);
nextStart += attrib.buffer.capacity() * Buffers.SIZEOF_FLOAT;
}
}
/**
* A utility method to load vertex data into an OpenGL "vertex array object" (VAO) for efficient
* rendering. The VAO stores several "vertex buffer objects" (VBOs) that contain the vertex
* attribute data.
*
* @param data reference to the vertex data to be loaded into a VAO
*/
private void initArrayBuffer(GLVertexData data) {
// Make a vertex array object (VAO) for this vertex data
// and store a reference to it
GLVertexArrayObject vao = new GLVertexArrayObject(gl, data.getElements().size() + 1);
data.setVAO(vao);
// Bind (activate) the VAO for the vertex data in OpenGL.
// The subsequent OpenGL operations on VBOs will be recorded (stored)
// in the VAO.
vao.bind();
// Store all vertex attributes in vertex buffer objects (VBOs)
ListIterator<VertexData.VertexElement> itr = data.getElements().listIterator(0);
data.getVAO().rewindVBO();
while (itr.hasNext()) {
VertexData.VertexElement e = itr.next();
// Bind the vertex buffer object (VBO)
gl.glBindBuffer(GL3.GL_ARRAY_BUFFER, data.getVAO().getNextVBO());
// Upload vertex data
gl.glBufferData(
GL3.GL_ARRAY_BUFFER,
e.getData().length * 4,
FloatBuffer.wrap(e.getData()),
GL3.GL_DYNAMIC_DRAW);
}
// Bind the default vertex buffer objects
gl.glBindBuffer(GL3.GL_ARRAY_BUFFER, 0);
// Store the vertex data indices into the last vertex buffer
gl.glBindBuffer(GL3.GL_ELEMENT_ARRAY_BUFFER, data.getVAO().getNextVBO());
gl.glBufferData(
GL3.GL_ELEMENT_ARRAY_BUFFER,
data.getIndices().length * 4,
IntBuffer.wrap(data.getIndices()),
GL3.GL_DYNAMIC_DRAW);
// Bind the default vertex array object. This "deactivates" the VAO
// of the vertex data
gl.glBindVertexArray(0);
}
private void initializeVertexBuffer(GL3 gl3) {
gl3.glGenBuffers(1, IntBuffer.wrap(vertexBufferObject));
gl3.glBindBuffer(GL3.GL_ARRAY_BUFFER, vertexBufferObject[0]);
{
FloatBuffer buffer = GLBuffers.newDirectFloatBuffer(vertexData);
gl3.glBufferData(GL3.GL_ARRAY_BUFFER, vertexData.length * 4, buffer, GL3.GL_STATIC_DRAW);
}
gl3.glBindBuffer(GL3.GL_ARRAY_BUFFER, 0);
}
