--- title: "Emission" url: "https://help.maxon.net/c4d/en-us/Content/html/OFPLIQUIDFILLEMITTER-FP_LIQUIDFILLEMITTER_MESH.html" section_path: "Simulate Menu > The Simulation System > Particle Emitter > Liquid Fill Emitter > Emission" element_id: "OFPLIQUIDFILLEMITTER" group_id: "FP_LIQUIDFILLEMITTER_MESH" description: "These settings are mainly used to define when and in which volume the liquid particles are generated and how they are to be arranged in the volume." --- ## Emission These settings are mainly used to define when and in which volume the liquid particles are generated and how they are to be arranged in the volume. ### Geometry Parameter ID: `FP_GEOMETRY_SOURCE_LINK` Here you assign the object in whose volume the liquid particles are to be created. It should be a closed volume, such as a sphere or a cube. If an object is already selected when the *Liquid Fill Emitter* is called up, this is automatically used as the geometry. Otherwise, simply drag and drop the relevant object from the *Object Manager* into this field. ### Pattern Parameter ID: `FP_LIQUIDFILLEMITTER_MESH_SCATTER` The volume of the assigned geometry is filled with a regular grid of liquid particles instead of using random positions for the particles. This prevents the particles from overlapping as soon as they are generated, which would lead to an unstable start of the fluid simulation. The following options are available: - *Grid*: The liquid particles are arranged three-dimensionally in regular rows and columns. The distances between the particles can be specified either depending on the **Default Radius** setting of the [Simulation Scene](https://help.maxon.net/c4d/en-us/Content/html/OPBDSCENE.html.md) or the [Scene Settings](https://help.maxon.net/c4d/en-us/Content/html/OPBDSCENE-PBDSCENE_LIQUIDS_GROUP.html.md) or also individually via the subsequent **Distance** value in the *Emission* settings of the emitter. - *Sphere Packing*: In this mode too, either the **Default Radius** for the liquid particles from the settings of the active simulation configuration or an individual **Distance** configured via the *Emission* settings of this emitter can be used. The arrangement of the particles is identical to the familiar *Honeycomb* arrangement, which is also available on the MoGraph [Cloner Object](https://help.maxon.net/c4d/en-us/Content/html/OMOGRAPH_CLONER-ID_OBJECTPROPERTIES.html.md). Compared to the *Grid Pattern*, the volume to be filled is filled even more effectively here. This means that even more particles fit into the same volume. ![Image: 2025-3_LiquidFillEmitter_Pattern_2.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2025-3_LiquidFillEmitter_Pattern_2.png)\ Here, a simple box is filled with liquid particles. The Grid option was used on the left and the Sphere Packing option on the right. As can be seen in the illustration above and the video below, the available volume of the assigned geometry is utilized even more optimally with *Sphere Packing*. Even more particles fit into the same volume without overlapping. The level of detail and the amount of simulated liquid can therefore be even greater with this arrangement compared to the simple *Grid*. [Video: 2025-3_LiquidFillEmitter_Pattern_01.mp4](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2025-3_LiquidFillEmitter_Pattern_01.mp4) A simulation with identical settings. The only difference is that the **Grid** pattern was used on the left and the **Sphere Packing** pattern on the right. With the latter, there is more space for liquid particles in the same volume, which leads to more liquid volume. ### Resolution Parameter ID: `FP_LIQUIDFILLEMITTER_MESH_RESOLUTION` This setting determines which spacing should be used within the selected pattern. - *Simulation Scene*: The distances in the selected pattern are automatically adjusted to the **Default Radius** of the [Simulation Scene](https://help.maxon.net/c4d/en-us/Content/html/OPBDSCENE.html.md) or the [Scene Settings](https://help.maxon.net/c4d/en-us/Content/html/OPBDSCENE-PBDSCENE_LIQUIDS_GROUP.html.md). If this default radius is actually used for the liquid particles (the [Liquify Modifier](https://help.maxon.net/c4d/en-us/Content/html/OFPLIQUIFY.html.md) also allows the alternative use of an individual **Radius** value configured on the emitter for the liquid particles, for example), this always results in the smallest possible distance between the generated particles. - *Override*: An individual **Distance** can be used to specify the spacing of the particles in the selected pattern. ### Distance Parameter ID: `FP_LIQUIDFILLEMITTER_MESH_RESOLUTION_DISTANCE` · Range: [0..+∞m] In the *Override* **Resolution** setting, an individual distance between the liquid particles in the selected **Pattern** can be selected. Make sure that the liquid particles react with repulsion to overlapping. Therefore, always select distances that are at least twice the particle **adius** used. The following illustration shows how this distance is applied depending on the selected **Pattern**. For the **Grid** *Pattern*, **Distance** corresponds to the distance between the particles in both the horizontal and vertical directions (indicated by the red edges on the left in the figure). For the *Sphere Packing* **Pattern**, however, the **Distance** is applied diagonally, i.e. between the particles of different depths and heights in the grid (shown on the right in the figure by the red lines). ![Image: 2025-3_LiquidFillEmitter_Distance_01.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2025-3_LiquidFillEmitter_Distance_01.png)\ The red lines here indicate how the spacing is used for the selected **Pattern** between the particles. The Grid **Pattern** can be seen on the left and the Sphere Packing **Pattern** on the right. ### Fill Direction Parameter ID: `FP_LIQUIDFILLEMITTER_FILL_DIRECTION` This and the following two settings are helpful if only a part of the assigned **Geometry** is to be filled with a liquid. For these cases, select the axis direction along which the filling should take place here. You define whether this is to be the local axis directions of the geometry or the directions of the world axes via **Fill Direction Space**.\ With the default setting **Fill Direction** *+Y* in conjunction with *Global* **Fill Direction Space**, the **Geometry** is always filled from bottom to top, regardless of how the **Geometry** object was rotated in space. The liquid level therefore always remains parallel to the horizon of the scene (world XZ plane).\ By reducing the **Fill Percentage**, only part of the **Geometry** can be filled with the liquid. This can be helpful if, for example, you want to optimize the volume or the number of particles in the liquid, or if the assigned **Geometry** is simply larger than the volume of liquid required. ### Fill Direction Space Parameter ID: `FP_LIQUIDFILLEMITTER_FILL_SPACE` Here you specify the axis system to be used for evaluating the **Fill Direction**: - *Local*: The axis directions of the assigned **Geometry** object are evaluated - *Global*: The world axis directions are evaluated here. The rotation of the **Geometry** axis system therefore no longer plays a role. ![Image: 2026-1_LiquidFillEmitter_Space_01.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2026-1_LiquidFillEmitter_Space_01.png)\ Here, a cube was assigned as the **Geometry** and 60% of it was filled with particles along the positive Y-axis. Since the **Global** axis system was specified as the reference, the liquid level remains parallel to the horizon of the scene even after the cube has been rotated. ### Fill Percentage Parameter ID: `FP_LIQUIDFILLEMITTER_FILL_PERCENTAGE` · Range: [0..100%] Percentage values below 100% mean that only a correspondingly reduced part of the **Geometry** volume can be filled with liquid particles. The two previous settings define the reference system and the axis direction in which the **Geometry** is to be filled. ### Enabled Parameter ID: `FP_EMITTER_EMISSION_ENABLED` This option switches the emitter function on or off. Only when switched on can particles be generated at the emitter for the specified **Start Frame**. ### Start Frame Parameter ID: `FP_EMITTER_EMISSION_START` If the **Enabled** option is switched on, you can enter an frame number for the animation where the liquid particles are to be generated. The *Liquid Fill Emitter* only ever generates particles once for the specified animation frame. If a volume is to emit liquid particles several times within a simulation, several *Liquid Fill Emitters* with different **Start  Frame** specifications must be used. ### Group Parameter ID: `FP_EMITTER_ATTRIBUTES_GROUP_LINK` Liquid particles are managed in the same [Particle Groups](https://help.maxon.net/c4d/en-us/Content/html/OFP_Groups_Main.html.md) that are also used for standard particles. When a *Liquid Fill Emitter* is called up, a new *Particle Group* is automatically created in which these particles are managed. The link to this group is automatically entered here, but can also be changed individually, e.g. by dragging and dropping another existing *Particle Group*. The eyedropper symbol is also available behind the **Group** field. If you click on this, you can then click on a *Particle Group* in the *Object Manager* that you want to link as a group. In addition, a new particle group can be created at any time by clicking on the **Create Group** button and automatically linked here. In the context menu, which opens by clicking on the small triangle symbol to the right of the **Group** field, you will find further commands for deleting the link to a Particle Group, as well as for displaying or selecting the linked *Particle Group*. ### Create Group Parameter ID: `FP_EMITTER_ATTRIBUTES_GROUP_CREATE` This can be used to create a new *Particle Group* and automatically link it to this emitter in the **Group** field. The newly emitted liquid particles are then automatically managed by this group. ![Image: subgroup.gif](https://help.maxon.net/c4d/en-us/Content/Resources/Images/subgroup.gif)\ Density Distribution In this section you will find options to influence the areas of the assigned geometry in which the newly created particles are to be created. Comparable options can also be found on the other emitters for standard particles. ### Distribution Parameter ID: `FP_EMITTER_EMISSION_PULSE_DISTRIBUTION` - *Uniform*: The particles are created within the entire geometry volume according to the selected **Pattern**. ![Image: 2025-3_LiquidFillEmitter_Distribution_01.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2025-3_LiquidFillEmitter_Distribution_01.png)\ The assigned volume is filled completely and evenly according to the selected pattern. - *Noise*: The *Noise* settings known from other places are offered to describe the pattern and size of a spatial structure. Particles then only occur within the assigned volume where values above 0 occur in this *Noise* structure. The full particle density - as it is also calculated in *Uniform* mode - can then only be observed where the *Noise* structure reaches its maximum values. At the intermediate *Noise* levels, i.e. values between 0 and 1, correspondingly fewer new particles are created in these areas. The basic structure of the particle placement otherwise remains identical to the emission in *Uniform* mode. ![Image: 2025-3_LiquidFillEmitter_Distribution_02.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2025-3_LiquidFillEmitter_Distribution_02.png)\ Here, the emission in a cube was limited by a noise structure with increased contrast. - *Field*: The values of [Field Objects](https://help.maxon.net/c4d/en-us/Content/html/58455.html.md) can be used to control the emission density. Similar to the use of a Noise structure, the new particles are initially positioned evenly on the emitter. In the second step, the falloff values of the assigned Field objects are evaluated. If the particle density is below the field value at the corresponding position, the new particles are automatically deleted there. The basic structure of the particle placement otherwise remains identical to the emission in *Uniform* mode. ![Image: 2025-3_LiquidFillEmitter_Distribution_03.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2025-3_LiquidFillEmitter_Distribution_03.png)\ Here, the emission in a box was limited by an assigned sphere field. ![Image: subgroup.gif](https://help.maxon.net/c4d/en-us/Content/Resources/Images/subgroup.gif)\ Noise These settings are only visible if you activate *Noise* for **Distribution**. ### Seed Parameter ID: `FP_EMITTER_EMISSION_SEED` · Range: [-2147483648..2147483647] The calculation of the Noise pattern is based on this value. A change in the **Seed** value will also leads to a recalculation of the selected noise structure. ### Noise Type Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_MODE` Here you can choose the right one from the various patterns. These are three-dimensional structures that can be configured in the axis system of the emitter or the world and with individual scaling along all axis directions. It is also possible to evolve these patterns automatically: ![Image: 2024-4_Particles_BasicEmitter_04_.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2024-4_Particles_BasicEmitter_04_.png) ![Image: 2024-4_Particles_BasicEmitter_05_.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2024-4_Particles_BasicEmitter_05_.png) ![Image: 2024-4_Particles_BasicEmitter_06_.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2024-4_Particles_BasicEmitter_06_.png) ![Image: 2024-4_Particles_BasicEmitter_07_.png](https://help.maxon.net/c4d/en-us/Content/Resources/Images/2024-4_Particles_BasicEmitter_07_.png) ### Noise Space Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_SPACE` Here you can select whether the noise structure should move with the local system of the emitter or whether it should be a stationary noise whose origin lies in the global world axis system. ### Octaves Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_OCTAVES` · Range: [1.00..20.00] This defines the amount of detail in the Noise structure. Larger values create correspondingly more variations in the pattern. Small values lead to a loss of contrast and details, as well as to a softening of the structure. This setting is not available for the Noise Types *Box*, *Cell*, *Mod Noise*, *Perlin* and *VL Noise*. ### Relative Scale Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_GLOBAL_SCALE` · Range: [XYZ %] You can use these values to scale the Noise structure individually along the three spatial directions. Proportional scaling is also possible via the **Scale** value. ### Scale Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_SCALE` · Range: [-∞..+∞%] This allows the Noise to be scaled proportionally. Individual scaling for each of the three axis directions is also possible via **Relative Scale**. ### Animation Speed Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_FREQUENCY` · Range: [-∞..+∞] The Noise structures can also be changed over time. Use this value to specify the speed of these changes. By default, 0 is used here, which results in a static structure. As the *Liquid Fill Emitter* only generates particles for one simulation frame by default, the animation of the Noise structure does not play a major role. However, it can be used to evaluate a variation of the Noise structure in different animation frames in the case of an emission triggered by keyframes. ### Loop Period Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_LOOP_PERIOD` · Range: [0.00..+∞] Almost all Noise Types (exception: *Electric* and *Gaseous*) offer this parameter, which causes the noise to loop after the defined time in seconds (**Animation Speed** must be greater than 0). The Noise state is then repeated after the entered seconds. A value of 0 turns this effect off. ### Uniform per Channel Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_UNIFORM` When activated, a determined noise value is used simultaneously for the red, green and blue color components. This results in pure gray or brightness values. If the option is switched off, individual Noise brightnesses are calculated for each of the three color components. The brightness of this color is then used for the final evaluation of the Noise value. ### Movement Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_MOVEMENT` · Range: [XYZ m] ### Speed Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_SPEED` · Range: [-∞..+∞%] These two parameters are used to move the Noise through the 3D space. **Movement** is a direction vector that you use to define the direction in which the Noise should move. Use the **Speed** value to regulate the movement speed of the Noise structure. Please note that the speed is also dependent on **Noise Space**, as the coordinate systems defined there can differ greatly from one another.\ As the *Liquid fill Emitter* only generates particles for one simulation frame by default, the animation of the Noise structure does not play a major role. However, it can be used to evaluate a variation of the Noise structure in different animation frames in the case of an emission triggered by keyframes. ### Low Clip Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_MIN` · Range: [0..100%] ### High Clip Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_MAX` · Range: [0..100%] This can be used to limit the brightness values that the Noise should provide. By default, **Low Clip** is 0% and **High Clip** is 100%. This means that all brightnesses can be output uncropped between 0% and 100% by the Noise. Increasing the **Low Clip** means that all brightnesses that are lower than defined for **Low Clip** are already output as black. Similarly, reducing **High Clip** results in gray values above the brightness of **High Clip** being output as white In fact, this mechanism can be used not only to sharpen a Noise structure and to strengthen the contrast, but also to invert the brightness values. To do this, simply reverse the original arrangement of the clipping values. With **Low Clip** 100% and **High Clip** 0%, you get an inverted Noise. ### Brightness Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_BRIGHTNESS` · Range: [-100..100%] This is used to adjust the general brightness value of the Noise. Values above 0% increase the brightness, values below 0% reduce it. ### Contrast Parameter ID: `FP_EMITTER_EMISSION_DENSITY_NOISE_CONTRAST` · Range: [-100..100%] This allows us to reduce or increase the contrast of the **Noise** Brightnesses. **Contrast** describes the range of brightness values. With a low contrast, the differences between the **Noise** Brightnesses supplied are therefore smaller. Greater **Contrast** leads to greater differences in brightness between the noise brightnesses calculated. This often results in the brightness transitions being more abrupt and less smooth compared to using a lower **Contrast**. In terms of emission, a greater contrast results in sharper boundaries between the areas on the emitter where particles are created and those that remain completely empty. ### Fields Parameter ID: `FP_EMITTER_EMISSION_DENSITY_FIELD` This area only appears when **Distribution** *Fields* is activated and enables the use of *Field objects* to assign an individual density within the particle distribution. Fields offer a wide range of shapes and also allow shaders and audio files to be evaluated, for example. In addition, several fields can be combined to use even more complex density control criteria. Similar to the use of noise structures, fields usually also generate values between 0.0 and 1.0. The larger the sampled field value, the more particles of the original, uniform density distribution are retained. Conversely, in areas with low field values, correspondingly fewer particles are produced at the emitter. This means that the originally configured number of new particles to be generated is lower after the fields have been evaluated. The operation of this area and the available objects and options correspond to the identical operating elements that you can also find on the Deformers, for example. Follow these links to find out everything you need to know about Fields and how to use them:\ If required, you can read all [about the various Field objects here](https://help.maxon.net/c4d/en-us/Content/html/58091.html.md).\ How to use the **Fields** area [is documented here](https://help.maxon.net/c4d/en-us/Content/html/OFALLOFF_STANDARD-FALLOFF_GROUPFALLOFF.html.md). > **Tip:** Note: > > The accuracy of Field sampling can be adjusted via the **Field Sampling Variance** in the [Particle Simulation Settings](https://help.maxon.net/c4d/en-us/Content/html/OPBDSCENE-PBDSCENE_FP_GROUP.html.md).