sl@0: /*
sl@0: * Copyright (c) 2003 Nokia Corporation and/or its subsidiary(-ies).
sl@0: * All rights reserved.
sl@0: * This component and the accompanying materials are made available
sl@0: * under the terms of the License "Eclipse Public License v1.0"
sl@0: * which accompanies this distribution, and is available
sl@0: * at the URL "http://www.eclipse.org/legal/epl-v10.html".
sl@0: *
sl@0: * Initial Contributors:
sl@0: * Nokia Corporation - initial contribution.
sl@0: *
sl@0: * Contributors:
sl@0: *
sl@0: * Description: Camera implementation
sl@0: *
sl@0: */
sl@0: 
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \file
sl@0:  * \brief Camera implementation
sl@0:  */
sl@0: 
sl@0: #ifndef M3G_CORE_INCLUDE
sl@0: #   error included by m3g_core.c; do not compile separately.
sl@0: #endif
sl@0: 
sl@0: #include "m3g_camera.h"
sl@0: 
sl@0: /* Internal frustum plane enumeration (and testing order!) */
sl@0: 
sl@0: #define NEAR_PLANE      0
sl@0: #define FAR_PLANE       1
sl@0: #define LEFT_PLANE      2
sl@0: #define RIGHT_PLANE     3
sl@0: #define BOTTOM_PLANE    4
sl@0: #define TOP_PLANE       5
sl@0: 
sl@0: /*----------------------------------------------------------------------
sl@0:  * Private functions
sl@0:  *--------------------------------------------------------------------*/
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Makes sure that the internal projection matrix is up-to-date
sl@0:  *        and checks if the camera has a zero view volume.
sl@0:  */
sl@0: static void m3gValidateProjectionMatrix(Camera *camera)
sl@0: {
sl@0:     M3Gint projType = camera->projType;
sl@0: 
sl@0:     /* The generic matrix is always valid, but for perspective and
sl@0:      * parallel we must regenerate the matrix */
sl@0:     
sl@0:     if (projType != M3G_GENERIC) {
sl@0:         M3Gfloat m[16];
sl@0: 
sl@0:         M3Gfloat clipNear = camera->clipNear;
sl@0:         M3Gfloat clipFar = camera->clipFar;
sl@0: 
sl@0:         if (projType == M3G_PERSPECTIVE) {
sl@0:             
sl@0:             M3Gfloat height = m3gTan(m3gMul(M3G_DEG2RAD * 0.5f,
sl@0:                                             camera->heightFov));
sl@0:             
sl@0:             m[0] = m3gRcp(m3gMul(camera->aspect, height));
sl@0:             m[1] = m[2] = m[3] = 0.f;
sl@0:             
sl@0:             m[4] = 0.f;
sl@0:             m[5] = m3gRcp(height);
sl@0:             m[6] = m[7] = 0.f;
sl@0:             
sl@0:             m[8] = m[9] = 0.f;
sl@0:             m[10] = m3gDiv(-m3gAdd(clipFar, clipNear),
sl@0:                            m3gSub(clipFar, clipNear));
sl@0:             m[11] = -1.f;
sl@0:             
sl@0:             m[12] = m[13] = 0.f;
sl@0:             m[14] = m3gDiv(m3gMul(m3gMul(-2.f, clipFar), clipNear),
sl@0:                            m3gSub(clipFar, clipNear));
sl@0:             m[15] = 0.f;
sl@0:         }
sl@0:         else if (projType == M3G_PARALLEL) {
sl@0: 
sl@0:             M3Gfloat height = camera->heightFov;
sl@0:             
sl@0:             m[0] = m3gDiv(2.f, m3gMul(camera->aspect, height));
sl@0:             m[1] = m[2] = m[3] = 0.f;
sl@0: 
sl@0:             m[4] = 0.f;
sl@0:             m[5] = m3gDiv(2.f, height);
sl@0:             m[6] = m[7] = 0;
sl@0:             
sl@0:             m[8] = m[9] = 0;
sl@0:             m[10] = m3gDiv(-2.f, m3gSub(clipFar, clipNear));
sl@0:             m[11] = 0.f;
sl@0:             
sl@0:             m[12] = m[13] = 0.f;
sl@0:             m[14] = m3gDiv(-m3gAdd(clipFar, clipNear),
sl@0:                            m3gSub(clipFar, clipNear));
sl@0:             m[15] = 1.f;
sl@0:         }
sl@0:         else {
sl@0:             M3G_ASSERT(M3G_FALSE); /* unknown projection type! */
sl@0:         }
sl@0:         m3gSetMatrixColumns(&camera->projMatrix, m); 
sl@0:     }
sl@0: 
sl@0:     {
sl@0:         M3GMatrix im;
sl@0:         if (!m3gMatrixInverse(&im, &camera->projMatrix)) {
sl@0:             camera->zeroViewVolume = M3G_TRUE;
sl@0:         }
sl@0:         else {
sl@0:             camera->zeroViewVolume = M3G_FALSE;
sl@0:         }
sl@0:     }
sl@0: 
sl@0:     camera->frustumPlanesValid = M3G_FALSE;
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Validates the cached view frustum planes
sl@0:  */
sl@0: static void m3gValidateFrustumPlanes(Camera *camera) 
sl@0: {
sl@0:     if (!camera->frustumPlanesValid) {
sl@0:         Vec4 *plane;
sl@0:         Vec4 rows[4];
sl@0:         
sl@0:         m3gGetMatrixRows(&camera->projMatrix, (M3Gfloat*) rows);
sl@0: 
sl@0:         plane = &camera->frustumPlanes[LEFT_PLANE];
sl@0:         *plane = rows[3];
sl@0:         m3gAddVec4(plane, &rows[0]);
sl@0: 
sl@0:         plane = &camera->frustumPlanes[RIGHT_PLANE];
sl@0:         *plane = rows[3];
sl@0:         m3gSubVec4(plane, &rows[0]);
sl@0: 
sl@0:         plane = &camera->frustumPlanes[BOTTOM_PLANE];
sl@0:         *plane = rows[3];
sl@0:         m3gAddVec4(plane, &rows[1]);
sl@0: 
sl@0:         plane = &camera->frustumPlanes[TOP_PLANE];
sl@0:         *plane = rows[3];
sl@0:         m3gSubVec4(plane, &rows[1]);
sl@0: 
sl@0:         plane = &camera->frustumPlanes[NEAR_PLANE];
sl@0:         *plane = rows[3];
sl@0:         m3gAddVec4(plane, &rows[2]);
sl@0: 
sl@0:         plane = &camera->frustumPlanes[FAR_PLANE];
sl@0:         *plane = rows[3];
sl@0:         m3gSubVec4(plane, &rows[2]);
sl@0: 
sl@0:         camera->frustumPlanesValid = M3G_TRUE;
sl@0:     }
sl@0: }
sl@0: 
sl@0: #undef NEAR_PLANE
sl@0: #undef FAR_PLANE
sl@0: #undef LEFT_PLANE
sl@0: #undef RIGHT_PLANE
sl@0: #undef BOTTOM_PLANE
sl@0: #undef TOP_PLANE
sl@0: 
sl@0: /*----------------------------------------------------------------------
sl@0:  * Internal functions
sl@0:  *--------------------------------------------------------------------*/
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Overloaded Object3D method.
sl@0:  *
sl@0:  * \param property      animation property
sl@0:  * \retval M3G_TRUE     property supported
sl@0:  * \retval M3G_FALSE    property not supported
sl@0:  */
sl@0: static M3Gbool m3gCameraIsCompatible(M3Gint property)
sl@0: {
sl@0:     switch (property) {
sl@0:     case M3G_ANIM_FAR_DISTANCE:
sl@0:     case M3G_ANIM_FIELD_OF_VIEW:
sl@0:     case M3G_ANIM_NEAR_DISTANCE:
sl@0:         return M3G_TRUE;
sl@0:     default:
sl@0:         return m3gNodeIsCompatible(property);
sl@0:     }
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Overloaded Object3D method.
sl@0:  *
sl@0:  * \param obj          Camera object
sl@0:  * \param property      animation property
sl@0:  * \param valueSize     size of value array
sl@0:  * \param value         value array
sl@0:  */
sl@0: static void m3gCameraUpdateProperty(Object *obj,
sl@0:                                     M3Gint property,
sl@0:                                     M3Gint valueSize,
sl@0:                                     const M3Gfloat *value)
sl@0: {
sl@0:     Camera *camera = (Camera *) obj;
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0:     M3G_ASSERT_PTR(value);
sl@0: 
sl@0:     switch (property) {
sl@0:     case M3G_ANIM_FAR_DISTANCE:
sl@0:         M3G_ASSERT(valueSize >= 1);
sl@0:         camera->clipFar =   (camera->projType == M3G_PERSPECTIVE)
sl@0:                             ? m3gClampFloatPositive(value[0])
sl@0:                             : value[0];
sl@0:         break;
sl@0:     case M3G_ANIM_FIELD_OF_VIEW:
sl@0:         M3G_ASSERT(valueSize >= 1);
sl@0:         camera->heightFov = (camera->projType == M3G_PERSPECTIVE)
sl@0:                             ? m3gClampFloat(value[0], 0.f, 180.f)
sl@0:                             : m3gClampFloatPositive(value[0]);
sl@0:         break;
sl@0:     case M3G_ANIM_NEAR_DISTANCE:
sl@0:         M3G_ASSERT(valueSize >= 1);
sl@0:         camera->clipNear =  (camera->projType == M3G_PERSPECTIVE)
sl@0:                             ? m3gClampFloatPositive(value[0])
sl@0:                             : value[0];
sl@0:         break;
sl@0:     default:
sl@0:         m3gNodeUpdateProperty(obj, property, valueSize, value);
sl@0:         return; /* don't invalidate the matrix */
sl@0:     }
sl@0: 
sl@0:     /* Validate the projection matrix if we changed any of the
sl@0:      * camera parameters */
sl@0: 
sl@0:     m3gValidateProjectionMatrix(camera);
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Overloaded Node method.
sl@0:  *
sl@0:  * Start render setup scene traversal.
sl@0:  *
sl@0:  * \param node Camera object
sl@0:  * \param toCamera transform to camera
sl@0:  * \param alphaFactor total alpha factor
sl@0:  * \param caller caller node
sl@0:  * \param renderQueue RenderQueue
sl@0:  *
sl@0:  * \retval M3G_TRUE continue render setup
sl@0:  * \retval M3G_FALSE abort render setup
sl@0:  */
sl@0: static M3Gbool m3gCameraSetupRender(Node *self,
sl@0:                                     const Node *caller,
sl@0:                                     SetupRenderState *s,
sl@0:                                     RenderQueue *renderQueue)
sl@0: {
sl@0:     Node *parent;
sl@0:     M3Gbool success = M3G_TRUE;
sl@0: 
sl@0:     /* Just do the parent node.  Note that we won't be needing the old
sl@0:      * state back after going up the tree, so we can overwrite it. */
sl@0:     
sl@0:     parent = self->parent;
sl@0: 
sl@0:     if (caller != parent && parent != NULL) {
sl@0:         Matrix t;
sl@0:         
sl@0:         M3G_BEGIN_PROFILE(M3G_INTERFACE(self), M3G_PROFILE_SETUP_TRANSFORMS);
sl@0:         if (!m3gGetInverseNodeTransform(self, &t)) {
sl@0:             return M3G_FALSE;
sl@0:         }
sl@0:         m3gMulMatrix(&s->toCamera, &t);
sl@0:         M3G_END_PROFILE(M3G_INTERFACE(self), M3G_PROFILE_SETUP_TRANSFORMS);
sl@0: 
sl@0:         /* The parent node will update the alpha factor and culling
sl@0:          * mask if necessary, so we need not touch those */
sl@0:         
sl@0:         success = M3G_VFUNC(Node, parent, setupRender)(parent,
sl@0:                                                        self, s, renderQueue);
sl@0:     }
sl@0: 
sl@0:     return success;
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Overloaded Object3D method.
sl@0:  *
sl@0:  * \param originalObj original Camera object
sl@0:  * \param cloneObj pointer to cloned Camera object
sl@0:  * \param pairs array for all object-duplicate pairs
sl@0:  * \param numPairs number of pairs
sl@0:  */
sl@0: static M3Gbool m3gCameraDuplicate(const Object *originalObj,
sl@0:                                   Object **cloneObj,
sl@0:                                   Object **pairs,
sl@0:                                   M3Gint *numPairs)
sl@0: {
sl@0:     Camera *original = (Camera *)originalObj;
sl@0:     Camera *clone = (Camera *)m3gCreateCamera(originalObj->interface);
sl@0:     *cloneObj = (Object *)clone;
sl@0:     if (*cloneObj == NULL) {
sl@0:         return M3G_FALSE;
sl@0:     }
sl@0: 
sl@0:     if (m3gNodeDuplicate(originalObj, cloneObj, pairs, numPairs)) {
sl@0:         clone->projType = original->projType;
sl@0:         clone->projMatrix = original->projMatrix;
sl@0:         clone->heightFov = original->heightFov;
sl@0:         clone->aspect = original->aspect;
sl@0:         clone->clipNear = original->clipNear;
sl@0:         clone->clipFar = original->clipFar;
sl@0:         clone->zeroViewVolume = original->zeroViewVolume;
sl@0:         return M3G_TRUE;
sl@0:     }
sl@0:     else {
sl@0:         return M3G_FALSE;
sl@0:     }
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Initializes a Camera object. See specification
sl@0:  * for default values.
sl@0:  *
sl@0:  * \param m3g           M3G interface
sl@0:  * \param camera        Camera object
sl@0:  */
sl@0: static void m3gInitCamera(Interface *m3g, Camera *camera)
sl@0: {
sl@0:     M3GMatrix m;
sl@0: 
sl@0:     /* Camera is derived from node */
sl@0:     m3gInitNode(m3g, &camera->node, M3G_CLASS_CAMERA);
sl@0: 
sl@0:     /* GENERIC, Identity */
sl@0:     m3gIdentityMatrix(&m);
sl@0:     m3gSetProjectionMatrix(camera, (const M3GMatrix *)&m);
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Sets camera matrix to OpenGL
sl@0:  * projection matrix.
sl@0:  *
sl@0:  * \param camera Camera object
sl@0:  */
sl@0: static void m3gApplyProjection(const Camera *camera)
sl@0: {
sl@0:     M3Gfloat t[16];
sl@0: 
sl@0:     m3gGetMatrixColumns(&camera->projMatrix, t);
sl@0:     
sl@0:     glMatrixMode(GL_PROJECTION);
sl@0:     glLoadMatrixf(t);
sl@0:     glMatrixMode(GL_MODELVIEW);
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Returns a pointer to the camera projection matrix
sl@0:  *
sl@0:  * The matrix <em>must not</em> be accessed directly, as only this
sl@0:  * function will ensure that the returned matrix has valid values in
sl@0:  * it.
sl@0:  * 
sl@0:  * \param camera Camera object
sl@0:  * \return a pointer to the projection matrix
sl@0:  */
sl@0: static const Matrix *m3gProjectionMatrix(const Camera *camera)
sl@0: {
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0: 
sl@0:     return &camera->projMatrix;
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \internal
sl@0:  * \brief Retrieves a pointer to the six camera space view frustum planes
sl@0:  */
sl@0: static const Vec4 *m3gFrustumPlanes(const Camera *camera)
sl@0: {
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0:     m3gValidateFrustumPlanes((Camera*) camera);
sl@0:     return camera->frustumPlanes;
sl@0: }
sl@0: 
sl@0: /*----------------------------------------------------------------------
sl@0:  * Virtual function table
sl@0:  *--------------------------------------------------------------------*/
sl@0: 
sl@0: static const NodeVFTable m3gvf_Camera = {
sl@0:     {
sl@0:         {
sl@0:             m3gObjectApplyAnimation,
sl@0:             m3gCameraIsCompatible,
sl@0:             m3gCameraUpdateProperty,
sl@0:             m3gObjectDoGetReferences,
sl@0:             m3gObjectFindID,
sl@0:             m3gCameraDuplicate,
sl@0:             m3gDestroyNode /* no extra clean-up for Camera */
sl@0:         }
sl@0:     },
sl@0:     m3gNodeAlign,
sl@0:     NULL, /* pure virtual DoRender */
sl@0:     m3gNodeGetBBox,
sl@0:     m3gNodeRayIntersect,
sl@0:     m3gCameraSetupRender,
sl@0:     m3gNodeUpdateDuplicateReferences,
sl@0:     m3gNodeValidate
sl@0: };
sl@0: 
sl@0: 
sl@0: /*----------------------------------------------------------------------
sl@0:  * Public API functions
sl@0:  *--------------------------------------------------------------------*/
sl@0: 
sl@0: /*!
sl@0:  * \brief Creates a Camera object.
sl@0:  *
sl@0:  * \param interface     M3G interface
sl@0:  * \retval Camera new Camera object
sl@0:  * \retval NULL Camera creating failed
sl@0:  */
sl@0: M3G_API M3GCamera m3gCreateCamera(M3GInterface interface)
sl@0: {
sl@0:     Interface *m3g = (Interface *) interface;
sl@0:     M3G_VALIDATE_INTERFACE(m3g);
sl@0: 
sl@0:     {
sl@0:         Camera *camera =  m3gAllocZ(m3g, sizeof(Camera));
sl@0: 
sl@0:         if (camera != NULL) {
sl@0:             m3gInitCamera(m3g, camera);
sl@0:         }
sl@0: 
sl@0:         return (M3GCamera) camera;
sl@0:     }
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \brief Sets a parallel projection.
sl@0:  *
sl@0:  * \param handle        Camera object
sl@0:  * \param height        height (=fovy)
sl@0:  * \param aspectRatio   viewport aspect ratio
sl@0:  * \param clipNear      near clipping plane
sl@0:  * \param clipFar       far clipping plane
sl@0:  */
sl@0: M3G_API void m3gSetParallel(M3GCamera handle,
sl@0:                             M3Gfloat height,
sl@0:                             M3Gfloat aspectRatio,
sl@0:                             M3Gfloat clipNear, M3Gfloat clipFar)
sl@0: {
sl@0:     Camera *camera = (Camera *) handle;
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0: 
sl@0:     if (height <= 0 || aspectRatio <= 0.0f) {
sl@0:         m3gRaiseError(M3G_INTERFACE(camera), M3G_INVALID_VALUE);
sl@0:         return;
sl@0:     }
sl@0: 
sl@0:     camera->projType   = M3G_PARALLEL;
sl@0:     camera->heightFov  = height;
sl@0:     camera->aspect     = aspectRatio;
sl@0:     camera->clipNear   = clipNear;
sl@0:     camera->clipFar    = clipFar;
sl@0: 
sl@0:     m3gValidateProjectionMatrix(camera);
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \brief Sets a perspective projection.
sl@0:  *
sl@0:  * \param handle        Camera object
sl@0:  * \param fovy          fovy
sl@0:  * \param aspectRatio   viewport aspect ratio
sl@0:  * \param clipNear      near clipping plane
sl@0:  * \param clipFar       far clipping plane
sl@0:  */
sl@0: M3G_API void m3gSetPerspective(M3GCamera handle,
sl@0:                                M3Gfloat fovy,
sl@0:                                M3Gfloat aspectRatio,
sl@0:                                M3Gfloat clipNear, M3Gfloat clipFar)
sl@0: {
sl@0:     Camera *camera = (Camera *) handle;
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0: 
sl@0:     if (fovy <= 0.0f || fovy >= 180.f
sl@0:         || aspectRatio <= 0.0f
sl@0:         || clipNear <= 0.0f || clipFar <= 0.0f) {
sl@0:         m3gRaiseError(M3G_INTERFACE(camera), M3G_INVALID_VALUE);
sl@0:         return;
sl@0:     }
sl@0: 
sl@0:     camera->projType   = M3G_PERSPECTIVE;
sl@0:     camera->heightFov  = fovy;
sl@0:     camera->aspect     = aspectRatio;
sl@0:     camera->clipNear   = clipNear;
sl@0:     camera->clipFar    = clipFar;
sl@0: 
sl@0:     m3gValidateProjectionMatrix(camera);
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \brief Sets a generic projection.
sl@0:  *
sl@0:  * \param handle        Camera object
sl@0:  * \param transform     projection matrix
sl@0:  */
sl@0: M3G_API void m3gSetProjectionMatrix(M3GCamera handle,
sl@0:                                     const M3GMatrix *transform)
sl@0: {
sl@0:     Camera *camera = (Camera *) handle;
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0: 
sl@0:     if (transform == NULL) {
sl@0:         m3gRaiseError(M3G_INTERFACE(camera), M3G_NULL_POINTER);
sl@0:         return;
sl@0:     }
sl@0:     
sl@0:     camera->projType = M3G_GENERIC;    
sl@0:     m3gCopyMatrix(&camera->projMatrix, transform);
sl@0:     
sl@0:     m3gValidateProjectionMatrix(camera);
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \brief Gets camera matrix.
sl@0:  *
sl@0:  * \param handle        Camera object
sl@0:  * \param transform     projection matrix to fill in
sl@0:  * \return              projection type
sl@0:  */
sl@0: M3G_API M3Gint m3gGetProjectionAsMatrix(M3GCamera handle,
sl@0:                                         M3GMatrix *transform)
sl@0: {
sl@0:     Camera *camera = (Camera *) handle;
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0: 
sl@0:     if (transform != NULL) {
sl@0:         /* Check for impossible projection matrix */
sl@0:         if (camera->projType != M3G_GENERIC && 
sl@0:             camera->clipFar == camera->clipNear) {
sl@0:             m3gRaiseError(M3G_INTERFACE(camera), M3G_ARITHMETIC_ERROR);
sl@0:             return 0;
sl@0:         }
sl@0: 
sl@0:         m3gCopyMatrix(transform, m3gProjectionMatrix(camera));
sl@0:     }
sl@0: 
sl@0:     return camera->projType;
sl@0: }
sl@0: 
sl@0: /*!
sl@0:  * \brief Gets camera parameters.
sl@0:  *
sl@0:  * \param handle        Camera object
sl@0:  * \param params        camera parameters to fill in
sl@0:  * \return              projection type
sl@0:  */
sl@0: M3G_API M3Gint m3gGetProjectionAsParams(M3GCamera handle, M3Gfloat *params)
sl@0: {
sl@0:     Camera *camera = (Camera *) handle;
sl@0:     M3G_VALIDATE_OBJECT(camera);
sl@0: 
sl@0:     if (params != NULL && camera->projType != M3G_GENERIC) {
sl@0:         params[0] = camera->heightFov;
sl@0:         params[1] = camera->aspect;
sl@0:         params[2] = camera->clipNear;
sl@0:         params[3] = camera->clipFar;
sl@0:     }
sl@0: 
sl@0:     return camera->projType;
sl@0: }
sl@0: