Class: RubyGL::IndexArray

Inherits:
Object
  • Object
show all
Defined in:
lib/rubygl/memory.rb

Instance Method Summary collapse

Constructor Details

#initialize(index_array) ⇒ IndexArray

Returns a new instance of IndexArray.



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# File 'lib/rubygl/memory.rb', line 79

def initialize(index_array)
    buff_ptr = FFI::MemoryPointer.new(:pointer)
    Native.glGenBuffers(1, buff_ptr)
    
    @buffer_id = buff_ptr.get_int(0)
    @buffer_elements = index_array.size
    @buffer_valid = true
    
    if @buffer_id <= 0 then
        raise "Could Not Allocate A GPU Buffer For The IndexArray Object"
    end
    
    Native.glBindBuffer(Native::GL_ELEMENT_ARRAY_BUFFER, @buffer_id)
    
    index_data = FFI::MemoryPointer.new(:uint, index_array.size)
    index_data.write_array_of_uint(index_array)
    
    Native.glBufferData(Native::GL_ELEMENT_ARRAY_BUFFER, index_data.size, index_data, Native::GL_STATIC_DRAW)
    
    Native.glBindBuffer(Native::GL_ELEMENT_ARRAY_BUFFER, 0)
end

Instance Method Details

#draw(components) ⇒ Object 



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# File 'lib/rubygl/memory.rb', line 101

def draw(components)
    raise "Call To IndexArray#draw On Frozen Object" unless @buffer_valid

    Native.glBindBuffer(Native::GL_ELEMENT_ARRAY_BUFFER, @buffer_id)

    Native.glDrawElements(Native::GL_TRIANGLES, @buffer_elements, Native::GL_UNSIGNED_INT, FFI::MemoryPointer::NULL)

    Native.glBindBuffer(Native::GL_ELEMENT_ARRAY_BUFFER, 0)
end

#release ⇒ Object

This frees the currently allocated GPU buffer for this IndexArray and invalidates this IndexArray object. Any calls to this object after calling this method will throw a runtime error.



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# File 'lib/rubygl/memory.rb', line 114

def release()
    raise "Call To IndexArray#release On Invalid Object" unless @buffer_valid

    buff_ptr = FFI::MemoryPointer.new(:uint)
    buff_ptr.write_uint(@buffer_id)
    
    Native.glDeleteBuffers(1, buff_ptr)
    
    @buffer_valid = false
end