diff -r 000000000000 -r 5d03bc08d59c m3g/m3gcore11/src/m3g_fog.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/m3g/m3gcore11/src/m3g_fog.c Tue Feb 02 01:47:50 2010 +0200 @@ -0,0 +1,424 @@ +/* +* Copyright (c) 2003 Nokia Corporation and/or its subsidiary(-ies). +* All rights reserved. +* This component and the accompanying materials are made available +* under the terms of the License "Eclipse Public License v1.0" +* which accompanies this distribution, and is available +* at the URL "http://www.eclipse.org/legal/epl-v10.html". +* +* Initial Contributors: +* Nokia Corporation - initial contribution. +* +* Contributors: +* +* Description: Fog implementation +* +*/ + + +/*! + * \internal + * \file + * \brief Fog implementation + */ + +#ifndef M3G_CORE_INCLUDE +# error included by m3g_core.c; do not compile separately. +#endif + +#include "m3g_fog.h" +#include "m3g_animationtrack.h" + +/*---------------------------------------------------------------------- + * Internal functions + *--------------------------------------------------------------------*/ + +/*! + * \internal + * \brief Destroys this Fog object. + * + * \param obj Fog object + */ +static void m3gDestroyFog(Object *obj) +{ + Fog *fog = (Fog *) obj; + M3G_VALIDATE_OBJECT(fog); + + m3gDestroyObject(&fog->object); +} + +/*! + * \internal + * \brief Overloaded Object3D method. + * + * \param property animation property + * \retval M3G_TRUE property supported + * \retval M3G_FALSE property not supported + */ +static M3Gbool m3gFogIsCompatible(M3Gint property) +{ + switch (property) { + case M3G_ANIM_COLOR: + case M3G_ANIM_DENSITY: + case M3G_ANIM_FAR_DISTANCE: + case M3G_ANIM_NEAR_DISTANCE: + return M3G_TRUE; + default: + return m3gObjectIsCompatible(property); + } +} + +/*! + * \internal + * \brief Overloaded Object3D method. + * + * \param self Fog object + * \param property animation property + * \param valueSize size of value array + * \param value value array + */ +static void m3gFogUpdateProperty(Object *self, + M3Gint property, + M3Gint valueSize, + const M3Gfloat *value) +{ + Fog *fog = (Fog *)self; + M3G_VALIDATE_OBJECT(fog); + M3G_ASSERT_PTR(value); + + switch (property) { + case M3G_ANIM_COLOR: + M3G_ASSERT(valueSize >= 3); + fog->color = m3gColor3f(value[0], value[1], value[2]) & M3G_RGB_MASK; + break; + case M3G_ANIM_DENSITY: + M3G_ASSERT(valueSize >= 1); + fog->density = (value[0] < 0.f) ? 0.f : value[0]; + break; + case M3G_ANIM_FAR_DISTANCE: + M3G_ASSERT(valueSize >= 1); + fog->end = value[0]; + break; + case M3G_ANIM_NEAR_DISTANCE: + M3G_ASSERT(valueSize >= 1); + fog->start = value[0]; + break; + default: + m3gObjectUpdateProperty(self, property, valueSize, value); + } +} + +/*! + * \internal + * \brief Overloaded Object3D method. + * + * \param originalObj original Fog object + * \param cloneObj pointer to cloned Fog object + * \param pairs array for all object-duplicate pairs + * \param numPairs number of pairs + */ +static M3Gbool m3gFogDuplicate(const Object *originalObj, + Object **cloneObj, + Object **pairs, + M3Gint *numPairs) +{ + Fog *original = (Fog *)originalObj; + Fog *clone = (Fog *)m3gCreateFog(originalObj->interface); + *cloneObj = (Object *)clone; + if (*cloneObj == NULL) { + return M3G_FALSE; + } + + if(m3gObjectDuplicate(originalObj, cloneObj, pairs, numPairs)) { + clone->color = original->color; + clone->density = original->density; + clone->start = original->start; + clone->end = original->end; + clone->mode = original->mode; + return M3G_TRUE; + } + else { + return M3G_FALSE; + } +} + +/*! + * \internal + * \brief Initializes a Fog object. See specification + * for default values. + * + * \param m3g M3G interface + * \param fog Fog object + */ +static void m3gInitFog(Interface *m3g, Fog *fog) +{ + /* Fog is derived from object */ + m3gInitObject(&fog->object, m3g, M3G_CLASS_FOG); + + fog->density = 1.0f; + fog->start = 0.0f; + fog->end = 1.0f; + fog->mode = M3G_LINEAR_FOG; +} + +/*! + * \internal + * \brief Applies fog to OpenGL. This is used for + * all Mesh objects. + * + * \param self Fog object + */ +static void m3gApplyFog(const Fog *self) +{ + if (self != NULL) { + GLfixed temp[4]; + + m3gGLColor(self->color, temp); + + switch (self->mode) { + case M3G_LINEAR_FOG: + glEnable(GL_FOG); + glFogf(GL_FOG_MODE, GL_LINEAR); + glFogf(GL_FOG_START, self->start); + glFogf(GL_FOG_END, self->end); + glFogxv(GL_FOG_COLOR, temp); + break; + case M3G_EXPONENTIAL_FOG: + glEnable(GL_FOG); + glFogf(GL_FOG_MODE, GL_EXP); + glFogf(GL_FOG_DENSITY, self->density); + glFogxv(GL_FOG_COLOR, temp); + break; + } + } + else { + glDisable(GL_FOG); + } + M3G_ASSERT_GL; +} + +/*! + * \internal + * \brief Applies fog to OpenGL. This is used for + * Sprite3D objects only. + * + * \param self Fog object + * \param eyeZ Eye space Z (e.g. after modelview) + * \param finalZ Final Z (e.g. after modelview and projection) + */ +static void m3gApplySpriteFog(const Fog *self, M3Gfloat eyeZ, M3Gfloat finalZ) +{ + if(self != NULL) { + M3Gint temp[4]; + M3Gfloat fogValue = 1; + + /* Calculate fog value and use OpenGL linear fog + * to result in same value. Sprites are drawn with + * identity MV and P and therefore the fog has to + * be adjusted like this */ + switch (self->mode) { + case M3G_LINEAR_FOG: + fogValue = m3gDiv(m3gAdd(self->end, eyeZ), m3gSub(self->end, self->start)); + break; + case M3G_EXPONENTIAL_FOG: + fogValue = m3gExp(m3gMul(self->density, eyeZ)); + break; + default: + M3G_ASSERT(M3G_FALSE); + break; + } + + m3gGLColor(self->color, temp); + + glEnable(GL_FOG); + glFogf(GL_FOG_MODE, GL_LINEAR); +#ifdef M3G_USE_NGL_API + /* NGL works differently in fog calculation */ + glFogf(GL_FOG_START, -m3gDiv(finalZ, fogValue)); +#else + glFogf(GL_FOG_START, m3gAbs(m3gDiv(finalZ, fogValue))); +#endif + glFogf(GL_FOG_END, 0.f); + glFogxv(GL_FOG_COLOR, temp); + } + else { + glDisable(GL_FOG); + } +} + +/*---------------------------------------------------------------------- + * Virtual function table + *--------------------------------------------------------------------*/ + +static const ObjectVFTable m3gvf_Fog = { + m3gObjectApplyAnimation, + m3gFogIsCompatible, + m3gFogUpdateProperty, + m3gObjectDoGetReferences, + m3gObjectFindID, + m3gFogDuplicate, + m3gDestroyFog +}; + + +/*---------------------------------------------------------------------- + * Public API functions + *--------------------------------------------------------------------*/ + +/*! + * \brief Creates a Fog object. + * + * \param interface M3G interface + * \retval Fog new Fog object + * \retval NULL Fog creating failed + */ +M3G_API M3GFog m3gCreateFog(M3GInterface interface) +{ + Interface *m3g = (Interface *) interface; + M3G_VALIDATE_INTERFACE(m3g); + + { + Fog *fog = m3gAllocZ(m3g, sizeof(Fog)); + + if (fog != NULL) { + m3gInitFog(m3g, fog); + } + + return (M3GFog) fog; + } +} + +/*! + * \brief Sets fog mode. + * + * \param handle Fog object + * \param mode fog mode + */ +M3G_API void m3gSetFogMode(M3GFog handle, M3Gint mode) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + /* Check for errors */ + if(mode < M3G_EXPONENTIAL_FOG || mode > M3G_LINEAR_FOG) { + m3gRaiseError(M3G_INTERFACE(fog), M3G_INVALID_VALUE); + return; + } + + fog->mode = mode; +} + +/*! + * \brief Gets fog mode. + * + * \param handle Fog object + * \return fog mode + */ +M3G_API M3Gint m3gGetFogMode(M3GFog handle) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + return fog->mode; +} + +/*! + * \brief Sets linear fog parameters. + * + * \param handle Fog object + * \param fogNear near distance + * \param fogFar far distance + */ +M3G_API void m3gSetFogLinear(M3GFog handle, M3Gfloat fogNear, M3Gfloat fogFar) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + fog->start = fogNear; + fog->end = fogFar; +} + +/*! + * \brief Gets linear fog parameters. + * + * \param handle Fog object + * \param which which parameter to return + * \arg M3G_GET_NEAR + * \arg M3G_GET_FAR + * \return near or far distance + */ +M3G_API M3Gfloat m3gGetFogDistance(M3GFog handle, M3Gint which) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + switch(which) { + case M3G_GET_NEAR: + return fog->start; + case M3G_GET_FAR: + default: + return fog->end; + } +} + +/*! + * \brief Sets exponential fog density. + * + * \param handle Fog object + * \param density fog density + */ +M3G_API void m3gSetFogDensity(M3GFog handle, M3Gfloat density) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + if(density < 0.f) { + m3gRaiseError(M3G_INTERFACE(fog), M3G_INVALID_VALUE); + return; + } + + fog->density = density; +} + +/*! + * \brief Gets exponential fog density. + * + * \param handle Fog object + * \return fog density + */ +M3G_API M3Gfloat m3gGetFogDensity(M3GFog handle) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + return fog->density; +} + +/*! + * \brief Sets fog color as RGB. + * + * \param handle Fog object + * \param rgb fog color as RGB + */ +M3G_API void m3gSetFogColor(M3GFog handle, M3Guint rgb) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + fog->color = rgb & M3G_RGB_MASK; +} + +/*! + * \brief Gets fog color as RGB. + * + * \param handle Fog object + * \return fog color as RGB + */ +M3G_API M3Guint m3gGetFogColor(M3GFog handle) +{ + Fog *fog = (Fog *) handle; + M3G_VALIDATE_OBJECT(fog); + + return fog->color; +} +