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	[No title]
		Phong Reflectance Model We are interested in global illumination and, consequently, desire a model for describing the reflectance of a surface compatible with the definition of the brdf that appears in the rendering equation.
		However, a physically plausible brdf based on the Phong shading model does exist and is often used in rendering algorithms.
		This is exactly how importance sampling works: we sample the space of all incoming rays of light in a way that favors the reflection distribution function, resulting in a provably unbiased estimate of the integral in the rendering equation that converges toward the actual answer quicker.
	www.cs.princeton.edu /courses/archive/fall02/cs526/snipets/importance.doc (1392 words)

	Phong
		A reflectance model conforming with the popular Phong model in which reflections are greatest in the “mirror” direction of a surface opposite the viewing direction with respect to the surface normal.
		Reflectance coefficients are provided which allow specification of the amount of ambient, diffuse and specular light reflected, corresponding to arguments "ambient factor", "diffuse factor" and "specular factor" respectively.
		The reflection is made sharper with large values of the exponent, such as 10.0.
	www.autotraxeda.com /docs/Active3D/Changing_objects/Editing_objects/Phong.htm (126 words)

	The RenderMan Academy - Phong Shading Model (Site not responding. Last check: )
		Since light is reflected equally in all directions the perceived illumination of the surface is not dependent on the position of the observer.
		Specular Reflection - Light is reflected mainly in the direction of the reflected ray and is attenuated by an amount dependent upon the physical properties of the surface.
		Since the light reflected from the surface is mainly in the direction of the reflected ray the position of the observer determines the perceived illumination of the surface.
	www.rendermanacademy.com /docs/phong_model.htm (1646 words)

	eScience Lectures Notes : Illumination and Shading
		Lambert's law states that the reflected energy from a small surface area in a particular direction is proportional to the cosine of the angle between that direction and the surface normal.
		The angle that the reflected ray forms with the surface normal is determined by the angle that the incoming ray forms with the surface normal, and the relative speeds of light of the mediums in which the incident and reflected rays propogate according to the following expression.
		Reflection is a very special case of Snell's Law where the incident light's medium and the reflected rays medium is the same.
	cs.anu.edu.au /escience/lecture/cg/Illumination/printCG.en.html (3637 words)

	Dr HS Fortuna Playstation 2 Linux Games Programming
		Where the bright spot appears on the material is a function of the position and orientation of the surface, the position of the light source and the position of the viewer.
		Specular reflection is merely the mirror reflection of the light source in a surface.
		We model the speed of that fall-off (and therefore the reflectivity of the surface) with the a shininess factor for the material of the surface.
	www.hsfortuna.pwp.blueyonder.co.uk /spclr/spclr.htm (899 words)

	Advanced Lighting and Antialiasing (Site not responding. Last check: )
		In the first pass diffuse reflectance is computed for each surface and then modulated by the texture colors to be applied to the surface and the result written to the color buffer.
		Light is hardly reflected from dielectrics such as glass at normal incidence, for example, while being almost totally reflected at glancing angles.
		At glancing angles, the light color is unaltered in reflection, but at normal incidence the light is modulated by the color of the metal.
	cips.eas.asu.edu /fagelgi/studies/others/aa_light/adv_lighting.html (3706 words)

	Plastic
		A reflectance model providing a specular effect which is similar to the Phong model.
		The sharpness of the specular reflection highlights can be controlled by means of argument "roughness".
		The reflection is made sharper with small values for the roughness, such as 0.1.
	www.autotraxeda.com /docs/Active3D/Changing_objects/Editing_objects/Plastic.htm (110 words)

	ReflectanceFunctions - OdWiki (Site not responding. Last check: )
		The direction of reflected light from a perfect mirror surface follows the very simple rule that the angle of incidence is equal to angle of reflection.
		Since the reflected intensity is defined as being the same in all directions, then it follows that it is independent of viewing angle -- i.e: a lambertian surface should look equally as bright from all viewing angles (within the hemisphere of illumination).
		Lambertian surfaces have the property that the amount of light reflected from a unit differential area toward the viewer is directly proportional to the cosine of the angle between the viewer and the surface normal.
	odforce.net /wiki/index.php/ReflectanceFunctions (9359 words)

	Reflectance (Site not responding. Last check: )
		, theintrinsic reflectance of the surface, irrespective of other parameters such asthe reflectance of the rear surface.
		The apparent reflectance for an ideal Lambertian surface is independent of theobserver.
		This contrasts with a shiny surface, where the apparent brightness is highest when the observing angle is equal tothe source angle.
	www.therfcc.org /reflectance-20338.html (161 words)

	Waterloo/CGL/Image Synthesis/Reflection Models (Site not responding. Last check: )
		Reflectance can be described using a bidirectional reflectance distribution function, which in general will depend on at least four degrees of freedom: the incident and view directions at a surface.
		Reflection models computed by such simulation can be quite complex even if the reflection model and the geometric model of the microgeometry are simple.
		The reflectance function for grass used above was obtained by shooting photons at microgeometry consisting of blades oriented randomly, and estimating the distribution of scattered photons.
	www.cgl.uwaterloo.ca /Projects/rendering/refl.html (577 words)

	[No title]
		R ranges from 0 to infinity, and the incident and reflected angles are measured as azimuth and elevation relative to the surface's normal (*,π/2) and some arbitrary axis along the surface (0, 0).
		For example, under Phong model, shown in Figure 1, R has a hemispherical shape with a fixed radius which is the sum of the ambient and diffuse light (which is constant for a fixed incident direction).
		Such a situation occurs, for example, when specular and retro reflection are both being used and the light is incident nearly normal to the surface, or when specular and grazing reflection are being used and the light nearly grazes the surface.
	www.cs.unc.edu /~feasel/classes/236/final (3106 words)

	Gouraud Shading, Flat Shading, etc...
		Phong shading yields substantial improvements over Gouraud shading when such illumination models are used, because highlights are reproduced more faithfully, as shown in Fig.
		Even with an illumination model that does not take into account specular reflectance, the results of normal-vector interpolation are in general superior to intensity interpolation, because an approximation to the normal is used at each point.
		As in Phong shading, the illumination model is evaluated at each pixel, but the interpolated dot products are used to avoid the expense of computing and normalizing any of the direction vectors.
	www.futuretech.blinkenlights.nl /gouraud.html (2421 words)

	9 Using Procedural Shaders with Global Illumination Algorithms
		Because the reflectance properties of real world surfaces are too complex to be described by a few parameters of some fixed reflection model, a physically-based scene description interface requires a procedural approach, like that available in the RenderMan interface.
		A sample shader using this modified illuminance construct to implement the well known Phong reflectance model is given in Figure 9.2.
		'' surface shader with 30% diffuse and 70% specular reflectance and a specular exponent of 3.
	graphics.cs.uni-sb.de /~slusallek/Doc/html/node14.html (4306 words)

	Untitled
		Phong shading (better job of handling specular) - uses several different reflectance models.
		We often use a cosine law (called the Lambertian law for diffuse reflection) to compute the brightness, such as b = I * (N.L) where N is the surface normal, L is the vector pointing from the center of the polygon to the light source, and I is the incoming light's intensity.
		In that model, specular light is allowed for, by computing a reflected ray R (see Assignment 2 below.) The cosine of the angle between the viewing direction and R is raised to some power n, for n between 1 and several hundred.
	longwood.cs.ucf.edu /~moshell/CAP5725/4000.week5.html (2093 words)

	The Cosine Lobe Model. (Site not responding. Last check: )
		First, it contains the Lambertian model of perfectly diffuse reflectance when the Phong exponent is null.
		It is capable of representing more generalized diffuse behavior, whose reflectance decreases exponentially according to the azimuthal angle theta.
		The classical Phong model has several difficulties -- among them, the apparent brightness decreases for glancing angles, exactly the opposite of the effect observed in nature.
	www.cs.utah.edu /~wmartin/lafortune (276 words)

	Basic Illumination Model
		The amount of light reflected from a unit differential area dA toward the viewer is directly proportional to the cosine of the angle between the the direction to the viewer and N
		Phong shading yields substantial improvements over Gouraud shading when illumination models with specular-reflectance terms are used, because highlights are reproduced more faithfully.
		However, if Phong shading is used, then the highlight will not be spreaded across the polygon, since interpolated normals will be used at each pixel.
	www.cs.nps.navy.mil /people/faculty/capps/4473/projects/01Summer/shading/Eray-LongVersion.htm (1515 words)

	Publications (Site not responding. Last check: )
		The course begins with the visual phenomena important to the perception of reflectance in real-world materials, which it uses as background for the underlying theory and derivation of common reflectance models.
		In terms of reflectance, most games to date use the Phong reflectance model or rely on strict intensity modulation to determine how surfaces reflect the light that strikes them.
		While this is not a bad thing, Phong reflectance and intensity modulation are limited in the type of lighting phenomena they are capable of simulating.
	www.cs.ucl.ac.uk /staff/J.Kautz/publications/index.html (4580 words)

	An Approach for Determining Phong Reflectance Parameters from Real Objects
		Modeling reflectance properties from real objects is useful for solving many practical problems, ranging from industrial inspection to computer graphics.
		This paper describes an automatic way to recover actual reflectance parameters, from range and intensity (or color) data acquired from objects.
		The proposed approach is based on Phong reflection model, since this model is usually preferred for computer graphics.
	csdl2.computer.org /persagen/DLAbsToc.jsp?resourcePath=/dl/proceedings/&toc=comp/proceedings/icpr/2000/0750/03/0750toc.xml&DOI=10.1109/ICPR.2000.903609 (204 words)

	Rendering Attributes (Site not responding. Last check: )
		This value tells how many reflections or refractions will be performed before the ray dies out.
		The face specular color, which is not used in the Phong model, is used to give color to the highlight in the Cook reflectance model.
		When rendering metallic faces, the simplest thing to do is to set the face specular color to the same color as the face color.
	www.vx.com /help/0356.htm (609 words)

	[No title]
		In Phong shading, we had a light source vector only (a unique vector was used to shade the point).
		This means that we ignored the reflection from bright surfaces in the scene.
		At each bounce, the light may be reflected in a random direction (diffuse) or it may be reflected near the mirror direction (diffuse).
	www.cim.mcgill.ca /~langer/557B/March20.html (1686 words)

	GurneyGallery (Site not responding. Last check: )
		The new toolset in tS5 proved useful in allowing the mesh to be created with the necessary detail, within the required timescale.
		Note that the mesh is designed for import and use in 3DS Max, so that only basic texturing has been used (only phong reflectance, and plain colour!).
		For these test shots, IBL lighting was used, as it gives a great sense of solidity to the object.
	www.tmgcgart.com /html/gurneygallery.htm (151 words)

	shader: "phong" (Site not responding. Last check: )
		Reflectance coefficients are provided which allow specification of the amount of ambient, diffuse and specular light reflected, corresponding to arguments
		The sharpness of the specular reflection highlights can be controlled by means of argument
		This model is suitable for shiny or highly pollished materials such as ceramic or glass.
	www.graphisoft.com /ftp/techsupport/documentation/developer_docs/BasicLibraryDoc/10/LightWorksIntegration/LW_Programmers_ref/phong.html (115 words)

	Graduate Student Seminar - Events - Department of Computing Science - University of Alberta
		Motivated by the primary goals of reconstructing the object and the parameters to a reflectance model, we take advantage of known lighting conditions in the error criteria.
		In particular, we assume that there is light variation, due to object rotation relative to the light source, allowing the recovery of shape in both textured and textureless regions.
		Results on real and synthetic images demonstrate that this method is capable of recovering the geometry of textureless surfaces and moderately textured surfaces, but is unstable in the recovery of deep concavities.
	www.cs.ualberta.ca /events/details.php?id=455 (321 words)

	Using the Modified Phong BRDF for Physically Based Rendering (Site not responding. Last check: )
		The first section presents the definition of the bidirectional reflection distribution function (brdf) of a surface and its physical properties.
		The third section goes into details about a specific reflectance model, the modified Phong brdf, with its definition, its properties and its use.
		The fourth section is devoted to alternative parameter spaces in which reflectance models can be sampled, either deterministically or stochastically.
	www.graphics.cornell.edu /~eric/Phong.html (193 words)

	[No title] (Site not responding. Last check: )
		The water used a base wrapped rough bump map I believe with a base Caligari phong reflectance, a solid color and no transparency.
		The third picture is the same as the second one in overall modeling and texturing, but I changed the background to the night sky similar to the first image, with a sun I made in Micrografx added in.
		The water's mirror coefficient allowed for the new reflections, and small adjustments to the lighting were made in order to emphasize the difference in time between it and the daytime version.
	www.angelfire.com /ma4/thehappydrink/art/spaceboatmodel.html (303 words)

	[No title]
		The torus is more than just texture mapped -- it is 'light sourced' using the Phong reflectance model with Phong interpolation.
		For each screen pixel, 16 distributed rays were shot into the scene from the center of projection and their average returned intensity was computed.
		ANIMATED GOURAUD-SHADED TORUS AND TWIST The torus and an interesting shape I call the 'twist' are animated and rendered using the Phong reflectance model with Gouraud interpolation.
	eric-schmidt.com /eric/demo/readme.txt (672 words)

	Lighting and Materials
		Dielectrics, such as glass and water, have reflectances that depend on viewing angle.
		These reflectances are modeled by the Fresnel Equations, which for the unpolarized case can be approximated by a polynomial developed by Schlick [
		To approximate the specular reflection of an area light source we add a Phong term to dielectrics as well.
	www.cs.utah.edu /vissim/papers/rtrt/node6.html (416 words)

	Labs 8 & 9: Illumination and Integration
		We used the Phong reflectance model, and implemented both flat and Phong shading.
		The options for the latter are flat and Phong, since these are the models we implemented.
		Here are two pictures, one flat and one phong shaded, of the sphere from the above animations with a specularity of only 10.
	www.sccs.swarthmore.edu /users/05/zap/labs/E26/lab8/index.html (1637 words)

	8.1.1 Phong Highlights with Texture
		One of the problems with the OpenGL lighting model is that specular reflectance is computed before textures are applied in the normal pipeline sequence.
		In the second pass the specular highlight is computed for each polygon and added to the image in the framebuffer using a blending function which sums 100% of the source fragment and 100destination pixels.
		Since the coordinates of the vector are interpolated across the polygon and used to lookup the highlight, a much more accurate sampling of the highlight is achieved compared to interpolation of the highlight value itself.
	www.opengl.org /resources/code/samples/advanced/advanced97/notes/node66.html (454 words)

	Pro/ENGINEER Forum: Phong Reflectance & transparency
		The best option I found was to create a custom color with the Photolux setting Reflectance set to "Phong" (I'm on Wildfire 3.0).
		I dont have WF3 so Im not sure what PHONG reflecting is. I am asuming its something like fresnal reflection.
		There needs to be something to reflect on it or it will simply just be transparent.
	www.mcadcentral.com /proe/forum/forum_posts.asp?TID=31036 (327 words)

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