Data Fields

Methods

{
  "name": "OglViewport",
  "namespace": "sofa::gl::component::rendering2d",
  "module": "Sofa.GL.Component.Rendering2D",
  "include": "sofa/gl/component/rendering2d/OglViewport.h",
  "doc": "Set an additional viewport into the main one.",
  "inherits": [
    "VisualManager"
  ],
  "templates": [],
  "data_fields": [
    {
      "name": "p_screenPosition",
      "type": "type::Vec<2, int>",
      "xmlname": "screenPosition",
      "help": "Viewport position"
    },
    {
      "name": "p_screenSize",
      "type": "type::Vec<2, unsigned int>",
      "xmlname": "screenSize",
      "help": "Viewport size"
    },
    {
      "name": "p_cameraPosition",
      "type": "type::Vec3",
      "xmlname": "cameraPosition",
      "help": "Camera's position in eye's space"
    },
    {
      "name": "p_cameraOrientation",
      "type": "type::Quat<SReal>",
      "xmlname": "cameraOrientation",
      "help": "Camera's orientation"
    },
    {
      "name": "p_cameraRigid",
      "type": "RigidCoord",
      "xmlname": "cameraRigid",
      "help": "Camera's rigid coord"
    },
    {
      "name": "p_zNear",
      "type": "double",
      "xmlname": "zNear",
      "help": "Camera's ZNear"
    },
    {
      "name": "p_zFar",
      "type": "double",
      "xmlname": "zFar",
      "help": "Camera's ZFar"
    },
    {
      "name": "p_fovy",
      "type": "double",
      "xmlname": "fovy",
      "help": "Field of View (Y axis)"
    },
    {
      "name": "p_enabled",
      "type": "bool",
      "xmlname": "enabled",
      "help": "Enable visibility of the viewport"
    },
    {
      "name": "p_advancedRendering",
      "type": "bool",
      "xmlname": "advancedRendering",
      "help": "If true, viewport will be hidden if advancedRendering visual flag is not enabled"
    },
    {
      "name": "p_useFBO",
      "type": "bool",
      "xmlname": "useFBO",
      "help": "Use a FBO to render the viewport"
    },
    {
      "name": "p_swapMainView",
      "type": "bool",
      "xmlname": "swapMainView",
      "help": "Swap this viewport with the main view"
    },
    {
      "name": "p_drawCamera",
      "type": "bool",
      "xmlname": "drawCamera",
      "help": "Draw a frame representing the camera (see it in main viewport)"
    }
  ],
  "links": [],
  "methods": [
    {
      "name": "init",
      "return_type": "void",
      "params": [],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "draw",
      "return_type": "void",
      "params": [
        {
          "name": "vparams",
          "type": "const core::visual::VisualParams *"
        }
      ],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "doInitVisual",
      "return_type": "void",
      "params": [
        {
          "name": "",
          "type": "const core::visual::VisualParams *"
        }
      ],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "preDrawScene",
      "return_type": "void",
      "params": [
        {
          "name": "vp",
          "type": "core::visual::VisualParams *"
        }
      ],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "drawScene",
      "return_type": "bool",
      "params": [
        {
          "name": "vp",
          "type": "core::visual::VisualParams *"
        }
      ],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "postDrawScene",
      "return_type": "void",
      "params": [
        {
          "name": "vp",
          "type": "core::visual::VisualParams *"
        }
      ],
      "is_virtual": true,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "isVisible",
      "return_type": "bool",
      "params": [
        {
          "name": "vparams",
          "type": "const core::visual::VisualParams *"
        }
      ],
      "is_virtual": false,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "public"
    },
    {
      "name": "renderToViewport",
      "return_type": "void",
      "params": [
        {
          "name": "vp",
          "type": "core::visual::VisualParams *"
        }
      ],
      "is_virtual": false,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "protected"
    },
    {
      "name": "renderFBOToScreen",
      "return_type": "void",
      "params": [
        {
          "name": "vp",
          "type": "core::visual::VisualParams *"
        }
      ],
      "is_virtual": false,
      "is_pure_virtual": false,
      "is_static": false,
      "access": "protected"
    }
  ],
  "description": "The `OglViewport` component in the SOFA framework is used to create an additional viewport within the main one, allowing for more flexible and complex rendering scenarios. It inherits from `VisualManager`, which suggests that it manages visual aspects of a scene. The component provides several data fields to customize its behavior:\n\n- **screenPosition**: Defines the position of the viewport.\n- **screenSize**: Specifies the size of the viewport.\n- **cameraPosition** and **cameraOrientation**: Define the camera's position and orientation within the viewport.\n- **zNear** and **zFar**: Set the near and far clipping planes for the camera.\n- **fovy**: Field of view along the Y-axis, crucial for perspective calculations.\n- **enabled**: Boolean to enable or disable the visibility of the viewport.\n- **advancedRendering**: If true, hides the viewport if advanced rendering is not enabled.\n- **useFBO**: Use Frame Buffer Object (FBO) for off-screen rendering.\n- **swapMainView**: Swap this viewport with the main view.\n- **drawCamera**: Draw a frame representing the camera position in the main viewport.\n\nThis component interacts primarily through methods like `init`, `draw`, and various lifecycle events such as `preDrawScene`, `postDrawScene`, and `doInitVisual`. These methods are inherited from the `VisualManager` class, allowing it to integrate seamlessly into SOFA's rendering pipeline.",
  "maths": "The `OglViewport` component in the SOFA framework does not directly contribute to any mathematical or physical equations related to finite element methods (FEM). Instead, it serves a purely graphical role by managing an additional viewport within the main one. The primary function of this component is to enhance visualization capabilities and allow for more complex rendering scenarios without affecting the underlying mechanics simulation. Here are some key points regarding its functionality:\n\n- **Viewport Positioning**: \nThe `screenPosition` field specifies the position \\((p_x, p_y)\\) of the viewport within the main window.\n- **Viewport Size**: The `screenSize` field defines the dimensions \\((w, h)\\) of the viewport.\n- **Camera Parameters**: The `cameraPosition`, `cameraOrientation`, and associated parameters (such as `zNear`, `zFar`, `fovy`) are used to define the perspective projection matrix for rendering within the specified viewport. These parameters determine how objects are transformed from 3D space into 2D screen coordinates.\n\n### Mathematical Context:\n- **Projection Matrix**: The camera parameters can be used to construct a perspective projection matrix \\(P\\). Given `fovy` (field of view along Y-axis), `aspectRatio` (width/height ratio), and `zNear`, `zFar`, the perspective matrix is defined as:\n\n\begin{equation}\n P = \n \\begin{pmatrix}\n \\frac{n}{w} & 0 & 0 & 0 \\\\\n 0 & \\frac{n}{h} & 0 & 0 \\\\\n 0 & 0 & -\\frac{(f+n)}{(f-n)} & -\\frac{2fn}{(f-n)} \\\\\n 0 & 0 & -1 & 0\n \\end{pmatrix}\n\tag{1}\n\text{where } n = zNear, f = zFar,\n w = aspectRatio * h.\n\tag{2}\n\tag{3}\n\tag{4}\n\tag{5}\n\tag{6}\n\n- **View Matrix**: The camera position and orientation can be used to construct the view matrix \\(V\\), which transforms points from world coordinates to eye (camera) coordinates. Given `cameraPosition` \\((x_c, y_c, z_c)\\) and `cameraOrientation` as a quaternion \\(q = [w, x, y, z]\\), the transformation involves translation and rotation operations.\n\n### Role in FEM Pipeline:\nThe `OglViewport` does not play a role in any part of the FEM simulation pipeline. It is entirely concerned with rendering aspects of the scene visualization. The methods such as `init`, `draw`, and others like `preDrawScene`, `postDrawScene`, etc., are related to integrating this component into SOFA's rendering process.\n\n### Numerical Methods:\nThe numerical aspect here pertains to graphics, where operations include matrix transformations for perspective projection and camera view. These operations ensure that the visual representation of the scene is correctly projected onto the specified viewport within the main window.\n\n### Integration with Lagrangian Mechanics Framework:\nThere is no direct integration into the Lagrangian mechanics framework since `OglViewport` is a visualization tool. Its primary purpose is to enhance how simulations are visually presented, without affecting any mechanical or numerical aspects of the simulation itself.",
  "abstract": "`OglViewport` creates an additional viewport within the main window in SOFA's rendering pipeline, managing its position, size, camera settings, and visibility.",
  "sheet": "# OglViewport\n\n## Overview\nThe `OglViewport` component manages an additional viewport within the main one, allowing for flexible visualization scenarios. It inherits from `VisualManager`, integrating seamlessly into SOFA's rendering process.\n\n## Parameters and Data\n- **screenPosition**: Defines the position \\\\( (p_x, p_y) \\\\) of the viewport within the main window.\n- **screenSize**: Specifies the dimensions \\\\( (w, h) \\\\) of the viewport.\n- **cameraPosition**: Camera's position in eye space.\n- **cameraOrientation**: Camera's orientation as a quaternion.\n- **zNear** and **zFar**: Near and far clipping planes for the camera.\n- **fovy**: Field of view along the Y-axis, used to construct the perspective projection matrix.\n- **enabled**: Boolean to enable or disable viewport visibility.\n- **advancedRendering**: If true, hides the viewport if advanced rendering is not enabled.\n- **useFBO**: Use Frame Buffer Object (FBO) for off-screen rendering.\n- **swapMainView**: Swap this viewport with the main view.\n- **drawCamera**: Draw a frame representing the camera position in the main viewport.\n\n## Practical Notes\nThe `OglViewport` component is primarily used to enhance visualization capabilities. Ensure that the parameters are set correctly for proper rendering, especially when using advanced features like FBOs or swapping with the main view."
}