![]() ![]() This is done via the AkGeometryParams::EnableDiffraction flag. Geometric diffraction can be used to affect the direct sound propagation path between the emitter and listener, but also the path of its early reflections, when used in conjunction with Reflect.Įach geometry set that is passed to Spatial Audio needs to say explicitly whether it should be considered for calculating diffraction paths. Also, it is good to use the efficient Rooms and Portals abstraction (see Rooms and Portals) in conjunction with Geometric Diffraction in order to reduce the computational complexity of the latter. Geometry passed to Spatial Audio should be kept as simple as possible. Warning: Geometric diffraction and transmission can be used to entirely replace your game engine's raycasting method for computing obstruction, however the performance cost grows with the complexity of the geometry. It shows a sound with a diffraction path, diffracting around the edges of a thin wall, and a transmission path with a transmission loss of 100%. The image below is a screenshot of the Game Object 3D Viewer in Wwise. Typically, transmission loss is modeled with a low-pass filter and a volume attenuation. Sound transmitting though an obstacle has a transmission loss coefficient applied to it, resulting from the surface properties assigned to the geometry via the API. Typically, diffraction results in low-pass filtering.Īdditionally, Spatial Audio computes sound paths going through geometry. The apparent angle of incidence of the emitter is modified accordingly, and the diffraction value is sent to Wwise where you may control how it ultimately affects the sound. When an emitter is hidden from a listener by an object, Spatial Audio computes paths along its edges and, if some are found, computes the diffraction coefficient resulting from the sound bending around these edges. As such, it can completely replace your game engine's raycasting methods for computing obstruction. Since different colors diffract by different amounts, white light seen through a diffraction grating will spread out into its component colors as shown in this YouTube of incandescent and florescent diffraction.The geometry passed to Wwise Spatial Audio may be used to simulate diffraction and transmission of sound. A diffraction grating is a piece of glass or plastic with a series of very small grooves, each of which acts like a slit.Why is the light pattern complicated instead of a simple spot? What is the difference in the light pattern between the single slits and the double slits? ![]() Finally the laser is shone through a series of double slits. Then the laser is shone through single openings of different sizes. The first is a square opening, the second a hexagonal opening. A red laser beam is shone through several different small openings. Notice that the plane waves on the right spread out into a circle on the left after passing through the small opening. You are looking down onto the surface of a tray of water. ![]() Here water waves travel through an opening about the same size as the wavelength and change their direction. Likewise sunsets are orange because when the sun is on the horizon the path the light travels to reach us passes through more atmosphere and even more violet/blue is removed. The sun looks a little more yellow than it really is because the violet/blue part of the spectrum has been removed (scattered out in other directions). Violet and a little blue light is scattered but since our eyes are not as sensitive to violet we see the blue. The sky is blue because clusters of nitrogen and oxygen molecules (which make up most of the atmosphere) have resonances at the same frequency of violet light. The wave is first absorbed and then re-emitted in all directions (or sometimes perpendicular to the incident direction). Scatteringis a similar phenomenon that occurs when a wave interacts with an object that has a resonance frequency the same as the wave frequency. We only notice diffraction when the opening or object is close to the size of the wavelength, so to see diffraction of light it needs to pass through a much smaller opening than a doorway. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |