tailieunhanh - LightWave 3D 8 Lighting Wordware game and graphics library phần 6

Nó là một kỹ thuật nhỏ rất linh hoạt có thể được sử dụng trong vô số cách. Hình ảnh đèn đường phố như nhìn từ máy bay trực thăng. Hoặc tưởng tượng hữu ích như thế nào hiệu ứng này có thể có được trong những ngày của Blade Runner khi một cảnh quan thành phố vào ban đêm được sáng tác chủ yếu của ánh sáng nguồn điểm sáng chỉ như thế này. | Color Mixing white light is whole with all the primaries at full saturation. If you remove all the green and all the blue then you have primary red. Certainly the final color is a highly saturated red but is primary red a more saturated color than white White is actually a highly saturated mix of the primaries. However for the purposes of individual hues we will accept that any color that moves toward white is less saturated. High Saturation Low Saturation Figure See color image. Value Value works similarly to saturation except that instead of the hue moving toward white the hue moves toward black. A higher value color is considered to be closer to the pure hue. For example a pure cyan is considered to be a color of a very high value. If that color were to become very dark getting closer to black then that color would be considered to have a very low value. High Value Low Value Figure See color image. In the business of lighting value is tied to light intensity as we know that a light that is colored black emits no light. As a matter of fact if you set a light to 1 000 000 intensity set that light s color to a value of 0 and shine it on a white 100 diffuse surface there will be no illumination on that white surface. So in fact there is more than one way of setting a final color value. You can set the value in the HSV color picker you can change the light s intensity or you can even change the diffuse value of the surface that the light is shining on. The diffuse value of a surface is a multiplier of how much illumination is applied to a surface. Less illumination means less color transmission to the surface. Less color transmission means a lower final value. 247 Chapter 19 How Hue Saturation and Value Interact Hue saturation and value are not completely independent values. They are interlinked through axes. Just like there are x y and z axes in LightWave s Layout and Modeler there are H S and V axes in the HSV color selection model. Figure Color .