In this chapter we'll cover another simple light source - directional light. It represents an infinite parallel light source, such as a floodlight. Its direction is determined by the rotation part of the transform matrix.
Specific parameters The LightDirect plugin type contains all the common parameters described in the section for Light Rectangle , along with the specific ones for Light Omni (except for decay). There are two more parameters specific for the directional light:
storeWithIrradianceMap - When this option is on and GI calculation is set to Irradiance map V-Ray will calculate the effects of this light and store them in the irradiance map. The result is that the irradiance map is computed more slowly but the rendering takes less time. You can also save the irradiance map and reuse it later. beamRadius - Radius of the beam around the light. This only determines where photons for caustics are shot from. Set to 0.0 if you want to disable the beam. For the full list of parameters, please refer to the LightDirect plugin description in API Reference Guides .
Example Here we'll show how to add a LightDirect to a scene.
Python <code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line"># Compatibility with Python 2.7.</span><span data-v-c2b1f83f="" class="line">from __future__ import print_function</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line"># The directory containing the vray shared object should be present in the PYTHONPATH environment variable.</span><span data-v-c2b1f83f="" class="line"># Try to import the vray module from VRAY_SDK/python, if it is not in PYTHONPATH</span><span data-v-c2b1f83f="" class="line">import sys, os</span><span data-v-c2b1f83f="" class="line">VRAY_SDK = os.environ.get('VRAY_SDK')</span><span data-v-c2b1f83f="" class="line">if VRAY_SDK:</span><span data-v-c2b1f83f="" class="line"> sys.path.append(os.path.join(VRAY_SDK, 'python'))</span><span data-v-c2b1f83f="" class="line">import vray</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">SCENE_PATH = os.path.join(os.environ.get('VRAY_SDK'), 'scenes')</span><span data-v-c2b1f83f="" class="line"># Change process working directory to SCENE_PATH in order to be able to load relative scene resources.</span><span data-v-c2b1f83f="" class="line">os.chdir(SCENE_PATH)</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line"># The renderer is automatically closed after the `with` block.</span><span data-v-c2b1f83f="" class="line">with vray.VRayRenderer() as renderer:</span><span data-v-c2b1f83f="" class="line"> # Register a simple log callback. Always useful for debugging.</span><span data-v-c2b1f83f="" class="line"> def dumpMsg(renderer, message, level, instant):</span><span data-v-c2b1f83f="" class="line"> if level == vray.LOGLEVEL_ERROR:</span><span data-v-c2b1f83f="" class="line"> print("[ERROR]", message)</span><span data-v-c2b1f83f="" class="line"> elif level == vray.LOGLEVEL_WARNING:</span><span data-v-c2b1f83f="" class="line"> print("[Warning]", message)</span><span data-v-c2b1f83f="" class="line"> elif level == vray.LOGLEVEL_INFO:</span><span data-v-c2b1f83f="" class="line"> print("[info]", message)</span><span data-v-c2b1f83f="" class="line"> # Uncomment for testing, but you might want to ignore these in real code</span><span data-v-c2b1f83f="" class="line"> #else: print("[debug]", message)</span><span data-v-c2b1f83f="" class="line"> renderer.setOnLogMessage(dumpMsg)</span><span data-v-c2b1f83f="" class="line"> # Load scene from a file.</span><span data-v-c2b1f83f="" class="line"> renderer.load(os.path.join(SCENE_PATH, 'lighting.vrscene'))</span><span data-v-c2b1f83f="" class="line"> # Remove original light source from the scene.</span><span data-v-c2b1f83f="" class="line"> del renderer.plugins["VRayLightDomeShape1"]</span><span data-v-c2b1f83f="" class="line"> # LightDirect is a light source plugin that can be used to create physically accurate lights that cast rays from a specific direction.</span><span data-v-c2b1f83f="" class="line"> light = renderer.classes.LightDirect()</span><span data-v-c2b1f83f="" class="line"> # Specify the light position, rotation and scale.</span><span data-v-c2b1f83f="" class="line"> light.transform = vray.Transform(</span><span data-v-c2b1f83f="" class="line"> vray.Matrix(</span><span data-v-c2b1f83f="" class="line"> vray.Vector(-0.9715043, -1.387779e-017, 0.2370218),</span><span data-v-c2b1f83f="" class="line"> vray.Vector(0.1674119, 0.7078983, 0.6861874),</span><span data-v-c2b1f83f="" class="line"> vray.Vector(-0.1677873, 0.7063142, -0.6877262)),</span><span data-v-c2b1f83f="" class="line"> vray.Vector(0, 107.949804287337, 0))</span><span data-v-c2b1f83f="" class="line"> # Specify the color of the light in RGB float values and alpha(1.0f)</span><span data-v-c2b1f83f="" class="line"> light.color = vray.AColor(1, 1, 1)</span><span data-v-c2b1f83f="" class="line"> # Specify the light intensity based on the 'units' parameter.</span><span data-v-c2b1f83f="" class="line"> light.intensity = 3</span><span data-v-c2b1f83f="" class="line"> # Controls the softness of the shadows. Bigger values will produce softer shadows.</span><span data-v-c2b1f83f="" class="line"> light.spreadAngle = 0.176327</span><span data-v-c2b1f83f="" class="line"> # Specify shadow offset from the surface. Helps to prevent polygonal shadow artifacts on low-poly surfaces.</span><span data-v-c2b1f83f="" class="line"> light.shadowBias = 0.02</span><span data-v-c2b1f83f="" class="line"> # Start rendering.</span><span data-v-c2b1f83f="" class="line"> renderer.startSync()</span><span data-v-c2b1f83f="" class="line"> # Wait for rendering to end.</span><span data-v-c2b1f83f="" class="line"> renderer.waitForRenderEnd()</span></code>
C++ <code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">#define VRAY_RUNTIME_LOAD_PRIMARY</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">#include "vraysdk.hpp"</span><span data-v-c2b1f83f="" class="line">#include "vrayplugins.hpp"</span><span data-v-c2b1f83f="" class="line">#include "utils.h"</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">using namespace VRay;</span><span data-v-c2b1f83f="" class="line">using namespace VRay::Plugins;</span><span data-v-c2b1f83f="" class="line">using namespace std;</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">const char *BASE_PATH = getenv("VRAY_SDK");</span><span data-v-c2b1f83f="" class="line">string SCENE_PATH = (BASE_PATH ? string(BASE_PATH) : string(".")) + PATH_DELIMITER + "scenes";</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">int main() {</span><span data-v-c2b1f83f="" class="line"> // Change process working directory to SCENE_PATH in order to be able to load relative scene resources.</span><span data-v-c2b1f83f="" class="line"> changeCurrentDir(SCENE_PATH.c_str());</span><span data-v-c2b1f83f="" class="line"> // Load V-Ray SDK library.</span><span data-v-c2b1f83f="" class="line"> VRayInit init(NULL, true);</span><span data-v-c2b1f83f="" class="line"> // Create an instance of VRayRenderer with default options.</span><span data-v-c2b1f83f="" class="line"> // The renderer is automatically closed at the end of the current scope.</span><span data-v-c2b1f83f="" class="line"> VRayRenderer renderer;</span><span data-v-c2b1f83f="" class="line"> // It's recommended to always have a console log</span><span data-v-c2b1f83f="" class="line"> renderer.setOnLogMessage(logMessage);</span><span data-v-c2b1f83f="" class="line"> // Load scene from a file.</span><span data-v-c2b1f83f="" class="line"> renderer.load("lighting.vrscene");</span><span data-v-c2b1f83f="" class="line"> // Remove original light source from the scene.</span><span data-v-c2b1f83f="" class="line"> renderer.deletePlugin("VRayLightDomeShape1");</span><span data-v-c2b1f83f="" class="line"> // LightDirect is a light source plugin that can be used to create physically accurate lights that cast rays from a specific direction.</span><span data-v-c2b1f83f="" class="line"> LightDirect light = renderer.newPlugin<LightDirect>();</span><span data-v-c2b1f83f="" class="line"> // Specify the light position, rotation and scale.</span><span data-v-c2b1f83f="" class="line"> light.set_transform(Transform(</span><span data-v-c2b1f83f="" class="line"> Matrix(</span><span data-v-c2b1f83f="" class="line"> Vector(-0.9715043, -1.387779e-017, 0.2370218),</span><span data-v-c2b1f83f="" class="line"> Vector(0.1674119, 0.7078983, 0.6861874),</span><span data-v-c2b1f83f="" class="line"> Vector(-0.1677873, 0.7063142, -0.6877262)),</span><span data-v-c2b1f83f="" class="line"> Vector(0.0, 107.949804287337, 0.0)));</span><span data-v-c2b1f83f="" class="line"> // Specify the color of the light in RGB float values and alpha(1.0f)</span><span data-v-c2b1f83f="" class="line"> light.set_color(AColor(1.0, 1.0, 1.0));</span><span data-v-c2b1f83f="" class="line"> // Specify the light intensity based on the 'units' parameter.</span><span data-v-c2b1f83f="" class="line"> light.set_intensity(3);</span><span data-v-c2b1f83f="" class="line"> // Controls the softness of the shadows. Bigger values will produce softer shadows.</span><span data-v-c2b1f83f="" class="line"> light.set_spreadAngle(0.176327f);</span><span data-v-c2b1f83f="" class="line"> // Specify shadow offset from the surface. Helps to prevent polygonal shadow artifacts on low-poly surfaces.</span><span data-v-c2b1f83f="" class="line"> light.set_shadowBias(0.02f);</span><span data-v-c2b1f83f="" class="line"> // Start rendering.</span><span data-v-c2b1f83f="" class="line"> renderer.startSync();</span><span data-v-c2b1f83f="" class="line"> // Wait for rendering to end.</span><span data-v-c2b1f83f="" class="line"> renderer.waitForRenderEnd();</span><span data-v-c2b1f83f="" class="line"> return 0;</span><span data-v-c2b1f83f="" class="line">}</span></code>
C#.NET <code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">using System;</span><span data-v-c2b1f83f="" class="line">using System.IO;</span><span data-v-c2b1f83f="" class="line">using VRay;</span><span data-v-c2b1f83f="" class="line">using VRay.Plugins;</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">namespace _07_direct</span><span data-v-c2b1f83f="" class="line">{</span><span data-v-c2b1f83f="" class="line"> class Program</span><span data-v-c2b1f83f="" class="line"> {</span><span data-v-c2b1f83f="" class="line"> static void Main(string[] args)</span><span data-v-c2b1f83f="" class="line"> {</span><span data-v-c2b1f83f="" class="line"> string SCENE_PATH = Path.Combine(Environment.GetEnvironmentVariable("VRAY_SDK"), "scenes");</span><span data-v-c2b1f83f="" class="line"> // Change process working directory to SCENE_PATH in order to be able to load relative scene resources.</span><span data-v-c2b1f83f="" class="line"> Directory.SetCurrentDirectory(SCENE_PATH);</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line"> // Create an instance of VRayRenderer with default options. The renderer is automatically closed after the `using` block.</span><span data-v-c2b1f83f="" class="line"> using (VRayRenderer renderer = new VRayRenderer())</span><span data-v-c2b1f83f="" class="line"> {</span><span data-v-c2b1f83f="" class="line"> // Add a listener for any type of log message.</span><span data-v-c2b1f83f="" class="line"> renderer.LogMessage += new EventHandler<MessageEventArgs>((source, e) =></span><span data-v-c2b1f83f="" class="line"> {</span><span data-v-c2b1f83f="" class="line"> // You can remove the if for testing, but you might want to ignore Debug in real code</span><span data-v-c2b1f83f="" class="line"> if (e.LogLevel != LogLevelType.Debug)</span><span data-v-c2b1f83f="" class="line"> {</span><span data-v-c2b1f83f="" class="line"> Console.WriteLine(String.Format("[{0}] {1}", e.LogLevel.ToString(), e.Message));</span><span data-v-c2b1f83f="" class="line"> }</span><span data-v-c2b1f83f="" class="line"> });</span><span data-v-c2b1f83f="" class="line"> // Load scene from a file.</span><span data-v-c2b1f83f="" class="line"> renderer.Load("lighting.vrscene");</span><span data-v-c2b1f83f="" class="line"> // Remove original light source from the scene.</span><span data-v-c2b1f83f="" class="line"> renderer.DeletePlugin("VRayLightDomeShape1");</span><span data-v-c2b1f83f="" class="line"> // LightDirect is a light source plugin that can be used to create physically accurate lights that cast rays from a specific direction.</span><span data-v-c2b1f83f="" class="line"> LightDirect light = renderer.NewPlugin<LightDirect>();</span><span data-v-c2b1f83f="" class="line"> // Specify the light position, rotation and scale.</span><span data-v-c2b1f83f="" class="line"> light.Transform = new Transform(</span><span data-v-c2b1f83f="" class="line"> new Matrix(</span><span data-v-c2b1f83f="" class="line"> new Vector(-0.9715043, -1.387779e-017, 0.2370218),</span><span data-v-c2b1f83f="" class="line"> new Vector(0.1674119, 0.7078983, 0.6861874),</span><span data-v-c2b1f83f="" class="line"> new Vector(-0.1677873, 0.7063142, -0.6877262)),</span><span data-v-c2b1f83f="" class="line"> new Vector(0, 107.949804287337, 0));</span><span data-v-c2b1f83f="" class="line"> // Specify the color of the light in RGB float values and alpha = 1.</span><span data-v-c2b1f83f="" class="line"> light.Color = new AColor(1, 1, 1);</span><span data-v-c2b1f83f="" class="line"> // Specify the light intensity based on the 'units' parameter.</span><span data-v-c2b1f83f="" class="line"> light.Intensity = 3;</span><span data-v-c2b1f83f="" class="line"> // Controls the softness of the shadows. Bigger values will produce softer shadows.</span><span data-v-c2b1f83f="" class="line"> light.SpreadAngle = 0.176327F;</span><span data-v-c2b1f83f="" class="line"> // Specify shadow offset from the surface. Helps to prevent polygonal shadow artifacts on low-poly surfaces.</span><span data-v-c2b1f83f="" class="line"> light.ShadowBias = 0.02F;</span><span data-v-c2b1f83f="" class="line"> // Start rendering.</span><span data-v-c2b1f83f="" class="line"> renderer.StartSync();</span><span data-v-c2b1f83f="" class="line"> // Wait for rendering to end.</span><span data-v-c2b1f83f="" class="line"> renderer.WaitForRenderEnd();</span><span data-v-c2b1f83f="" class="line"> }</span><span data-v-c2b1f83f="" class="line"> }</span><span data-v-c2b1f83f="" class="line"> }</span><span data-v-c2b1f83f="" class="line">}</span></code>
Node.js <code data-v-c2b1f83f=""><span data-v-c2b1f83f="" class="line">var path = require('path');</span><span data-v-c2b1f83f="" class="line">var vray = require(path.join(process.env.VRAY_SDK, 'node', 'vray'));</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">var SCENE_PATH = path.join(process.env.VRAY_SDK, 'scenes');</span><span data-v-c2b1f83f="" class="line">// Change process working directory to SCENE_PATH in order to be able to load relative scene resources.</span><span data-v-c2b1f83f="" class="line">process.chdir(SCENE_PATH);</span><span data-v-c2b1f83f="" class="line"></span><span data-v-c2b1f83f="" class="line">// Create an instance of VRayRenderer with default options.</span><span data-v-c2b1f83f="" class="line">var renderer = vray.VRayRenderer();</span><span data-v-c2b1f83f="" class="line">// It's recommended to always have a console log callback</span><span data-v-c2b1f83f="" class="line">renderer.on("logMessage", function(message, level, instant) {</span><span data-v-c2b1f83f="" class="line"> if (level == vray.LOGLEVEL_ERROR)</span><span data-v-c2b1f83f="" class="line"> console.log("[ERROR] ", message);</span><span data-v-c2b1f83f="" class="line"> else if (level == vray.LOGLEVEL_WARNING)</span><span data-v-c2b1f83f="" class="line"> console.log("[Warning] ", message);</span><span data-v-c2b1f83f="" class="line"> else if (level == vray.LOGLEVEL_INFO)</span><span data-v-c2b1f83f="" class="line"> console.log("[info] ", message);</span><span data-v-c2b1f83f="" class="line"> // Uncomment for testing, but you might want to ignore these in real code</span><span data-v-c2b1f83f="" class="line"> //else console.log("[debug] ", message);</span><span data-v-c2b1f83f="" class="line">});</span><span data-v-c2b1f83f="" class="line">// Load scene from a file asynchronously.</span><span data-v-c2b1f83f="" class="line">renderer.load("lighting.vrscene", function(err) {</span><span data-v-c2b1f83f="" class="line"> if (err) throw err;</span><span data-v-c2b1f83f="" class="line"> // Remove original light source from the scene.</span><span data-v-c2b1f83f="" class="line"> delete renderer.plugins["VRayLightDomeShape1"];</span><span data-v-c2b1f83f="" class="line"> // LightDirect is a light source plugin that can be used to create physically accurate lights that cast rays from a specific direction.</span><span data-v-c2b1f83f="" class="line"> var light = renderer.classes.LightDirect();</span><span data-v-c2b1f83f="" class="line"> // Specify the light position, rotation and scale.</span><span data-v-c2b1f83f="" class="line"> light.transform = vray.Transform(</span><span data-v-c2b1f83f="" class="line"> vray.Matrix(</span><span data-v-c2b1f83f="" class="line"> vray.Vector(-0.9715043, -1.387779e-017, 0.2370218),</span><span data-v-c2b1f83f="" class="line"> vray.Vector(0.1674119, 0.7078983, 0.6861874),</span><span data-v-c2b1f83f="" class="line"> vray.Vector(-0.1677873, 0.7063142, -0.6877262)),</span><span data-v-c2b1f83f="" class="line"> vray.Vector(0, 107.949804287337, 0));</span><span data-v-c2b1f83f="" class="line"> // Specify the color of the light in RGB float values and alpha(1.0f)</span><span data-v-c2b1f83f="" class="line"> light.color = vray.AColor(1, 1, 1);</span><span data-v-c2b1f83f="" class="line"> // Specify the light intensity based on the 'units' parameter.</span><span data-v-c2b1f83f="" class="line"> light.intensity = 3;</span><span data-v-c2b1f83f="" class="line"> // Controls the softness of the shadows. Bigger values will produce softer shadows.</span><span data-v-c2b1f83f="" class="line"> light.spreadAngle = 0.176327;</span><span data-v-c2b1f83f="" class="line"> // Specify shadow offset from the surface. Helps to prevent polygonal shadow artifacts on low-poly surfaces.</span><span data-v-c2b1f83f="" class="line"> light.shadowBias = 0.02;</span><span data-v-c2b1f83f="" class="line"> // Start rendering.</span><span data-v-c2b1f83f="" class="line"> renderer.start(function(err) {</span><span data-v-c2b1f83f="" class="line"> if (err) throw err;</span><span data-v-c2b1f83f="" class="line"> // Wait for rendering to end.</span><span data-v-c2b1f83f="" class="line"> renderer.waitForRenderEnd(function() {</span><span data-v-c2b1f83f="" class="line"> renderer.close();</span><span data-v-c2b1f83f="" class="line"> });</span><span data-v-c2b1f83f="" class="line"> });</span><span data-v-c2b1f83f="" class="line">});</span></code>
Result The scene used for this render is called "Lighting_Direct.vrscene" and can be found in the scene bundle (comments on the different parameters available inside).
As you can notice, the directional light produces a lot of noise initially.