SkyManager.cpp

Go to the documentation of this file.

/* Copyright (C) 2012 Wildfire Games.
 * This file is part of 0 A.D.
 *
 * 0 A.D. is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * 0 A.D. is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 * Sky settings, texture management and rendering.
 */

#include "precompiled.h"

#include <algorithm>

#include "lib/timer.h"
#include "lib/tex/tex.h"
#include "lib/res/graphics/ogl_tex.h"

#include "maths/MathUtil.h"

#include "ps/CStr.h"
#include "ps/CLogger.h"
#include "ps/Loader.h"
#include "ps/Filesystem.h"

#include "renderer/SkyManager.h"
#include "renderer/Renderer.h"

#include "graphics/Camera.h"
#include "graphics/LightEnv.h"
#include "graphics/ShaderManager.h"
#include "graphics/TextureManager.h"


///////////////////////////////////////////////////////////////////////////////////////////////
// SkyManager implementation


///////////////////////////////////////////////////////////////////
// String names for each image, in order of the IMG_ constants
const wchar_t* SkyManager::s_imageNames[numTextures] = {
    L"front",
    L"back",
    L"right",
    L"left",
    L"top"
};


///////////////////////////////////////////////////////////////////
// Construction/Destruction
SkyManager::SkyManager()
{
    m_RenderSky = true;

    m_SkySet = L"";

    m_HorizonHeight = -150.0f;
    
    m_SkyCubeMap = 0;
}


///////////////////////////////////////////////////////////////////
// Load all sky textures
void SkyManager::LoadSkyTextures()
{
    /*for (size_t i = 0; i < ARRAY_SIZE(m_SkyTexture); ++i)
    {
        VfsPath path = VfsPath("art/textures/skies") / m_SkySet / (Path::String(s_imageNames[i])+L".dds");

        CTextureProperties textureProps(path);
        textureProps.SetWrap(GL_CLAMP_TO_EDGE);
        CTexturePtr texture = g_Renderer.GetTextureManager().CreateTexture(textureProps);
        texture->Prefetch();
        m_SkyTexture[i] = texture;
    }*/
    
    ///////////////////////////////////////////////////////////////////////////
    // HACK: THE HORRIBLENESS HERE IS OVER 9000. The following code is a HUGE hack and will be removed completely
    // as soon as all the hardcoded GL_TEXTURE_2D references are corrected in the TextureManager/OGL/tex libs.
    
    glGenTextures(1, &m_SkyCubeMap);
    glBindTexture(GL_TEXTURE_CUBE_MAP, m_SkyCubeMap);
    
    int types[] = {
        GL_TEXTURE_CUBE_MAP_POSITIVE_X,
        GL_TEXTURE_CUBE_MAP_NEGATIVE_X,
        GL_TEXTURE_CUBE_MAP_POSITIVE_Z,
        GL_TEXTURE_CUBE_MAP_NEGATIVE_Z,
        GL_TEXTURE_CUBE_MAP_POSITIVE_Y,
        GL_TEXTURE_CUBE_MAP_NEGATIVE_Y
    };
    
    const wchar_t* images[numTextures+1] = {
        L"front",
        L"back",
        L"right",
        L"left",
        L"top",
        L"top"
    };
    
    for (size_t i = 0; i < numTextures+1; ++i)
    {
        VfsPath path = VfsPath("art/textures/skies") / m_SkySet / (Path::String(images[i])+L".dds");
        
        shared_ptr<u8> file;
        size_t fileSize;
        if (g_VFS->LoadFile(path, file, fileSize) < 0)
        {
            VfsPath path2 = VfsPath("art/textures/skies") / m_SkySet / (Path::String(images[i])+L".dds.cached.dds");
            if (g_VFS->LoadFile(path2, file, fileSize) < 0)
            {
                glDeleteTextures(1, &m_SkyCubeMap);
                LOGERROR(L"Error creating sky cubemap.");
                return;
            }
        }
        
        Tex tex;
        tex_decode(file, fileSize, &tex);
        
        tex_transform_to(&tex, (tex.flags | TEX_BOTTOM_UP | TEX_ALPHA) & ~(TEX_DXT | TEX_MIPMAPS));
        
        u8* data = tex_get_data(&tex);
        
        if (types[i] == GL_TEXTURE_CUBE_MAP_NEGATIVE_Y || types[i] == GL_TEXTURE_CUBE_MAP_POSITIVE_Y)
        {
            std::vector<u8> rotated(tex.dataSize);
        
            for (size_t y = 0; y < tex.h; ++y)
            {
                for (size_t x = 0; x < tex.w; ++x)
                {
                    size_t invx = y, invy = tex.w-x-1;
                    
                    rotated[(y*tex.w + x) * 4 + 0] = data[(invy*tex.w + invx) * 4 + 0];
                    rotated[(y*tex.w + x) * 4 + 1] = data[(invy*tex.w + invx) * 4 + 1];
                    rotated[(y*tex.w + x) * 4 + 2] = data[(invy*tex.w + invx) * 4 + 2];
                    rotated[(y*tex.w + x) * 4 + 3] = data[(invy*tex.w + invx) * 4 + 3];
                }
            }
            
            glTexImage2D(types[i], 0, GL_RGB, tex.w, tex.h, 0, GL_RGBA, GL_UNSIGNED_BYTE, &rotated[0]);
        }
        else
        {
            glTexImage2D(types[i], 0, GL_RGB, tex.w, tex.h, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);
        }
        
        tex_free(&tex);
    }
    
    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
    glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
    
    glBindTexture(GL_TEXTURE_2D, 0);
    ///////////////////////////////////////////////////////////////////////////
}


///////////////////////////////////////////////////////////////////
// Switch to a different sky set (while the game is running)
void SkyManager::SetSkySet( const CStrW& newSet )
{
    if(newSet == m_SkySet)
        return;
    
    if (m_SkyCubeMap)
    {
        glDeleteTextures(1, &m_SkyCubeMap);
        m_SkyCubeMap = 0;
    }
    
    m_SkySet = newSet;

    LoadSkyTextures();
}

///////////////////////////////////////////////////////////////////
// Generate list of available skies
std::vector<CStrW> SkyManager::GetSkySets() const
{
    std::vector<CStrW> skies;

    // Find all subdirectories in art/textures/skies

    const VfsPath path(L"art/textures/skies/");
    DirectoryNames subdirectories;
    if(g_VFS->GetDirectoryEntries(path, 0, &subdirectories) < 0)
    {
        LOGERROR(L"Error opening directory '%ls'", path.string().c_str());
        return std::vector<CStrW>(1, GetSkySet()); // just return what we currently have
    }

    for(size_t i = 0; i < subdirectories.size(); i++)
        skies.push_back(subdirectories[i].string());
    sort(skies.begin(), skies.end());

    return skies;
}

///////////////////////////////////////////////////////////////////
// Render sky
void SkyManager::RenderSky()
{
#if CONFIG2_GLES
#warning TODO: implement SkyManager::RenderSky for GLES
#else

    // Draw the sky as a small box around the camera position, with depth write enabled.
    // This will be done before anything else is drawn so we'll be overlapped by everything else.

    // Note: The coordinates for this were set up through a rather cumbersome trial-and-error 
    //       process - there might be a smarter way to do it, but this seems to work.

    // Do nothing unless SetSkySet was called
    if (m_SkySet.empty())
        return;

    glDepthMask( GL_FALSE );
    
    pglActiveTextureARB(GL_TEXTURE0_ARB);
    glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    
    // Translate so we are at the camera in the X and Z directions, but
    // put the horizon at a fixed height regardless of camera Y
    const CCamera& camera = g_Renderer.GetViewCamera();
    CVector3D pos = camera.m_Orientation.GetTranslation();
    
    glTranslatef( pos.X, m_HorizonHeight, pos.Z );

    // Rotate so that the "left" face, which contains the brightest part of each
    // skymap, is in the direction of the sun from our light environment
    glRotatef( 180.0f /*+ 45.0f*/ + RADTODEG(g_Renderer.GetLightEnv().GetRotation()), 0.0f, 1.0f, 0.0f );

    // Distance to draw the faces at
    const float D = 2000.0;
    
    CShaderProgramPtr shader;
    CShaderTechniquePtr skytech;
    
    if (g_Renderer.GetRenderPath() == CRenderer::RP_SHADER)
    {
        skytech = g_Renderer.GetShaderManager().LoadEffect(str_sky_simple);
        skytech->BeginPass();
        shader = skytech->GetShader();
        shader->BindTexture(str_baseTex, m_SkyCubeMap);
    }
    else
    {
        glDisable(GL_TEXTURE_2D);
        glEnable(GL_TEXTURE_CUBE_MAP);
        glBindTexture(GL_TEXTURE_CUBE_MAP, m_SkyCubeMap);
    }

    // GL_TEXTURE_CUBE_MAP_NEGATIVE_X
    glBegin(GL_QUADS);
        glTexCoord3f( +1, +1, +1 );  glVertex3f( -D, -D, -D ); 
        glTexCoord3f( +1, +1, -1 );  glVertex3f( -D, -D, +D ); 
        glTexCoord3f( +1, -1, -1 );  glVertex3f( -D, +D, +D ); 
        glTexCoord3f( +1, -1, +1 );  glVertex3f( -D, +D, -D ); 
    glEnd();

    // GL_TEXTURE_CUBE_MAP_POSITIVE_X
    glBegin(GL_QUADS);
        glTexCoord3f( -1, +1, -1 );  glVertex3f( +D, -D, +D ); 
        glTexCoord3f( -1, +1, +1 );  glVertex3f( +D, -D, -D ); 
        glTexCoord3f( -1, -1, +1 );  glVertex3f( +D, +D, -D ); 
        glTexCoord3f( -1, -1, -1 );  glVertex3f( +D, +D, +D ); 
    glEnd();
    
    // GL_TEXTURE_CUBE_MAP_NEGATIVE_Y
    glBegin(GL_QUADS);
        glTexCoord3f( -1, +1, +1 );  glVertex3f( +D, -D, -D ); 
        glTexCoord3f( -1, +1, -1 );  glVertex3f( +D, -D, +D ); 
        glTexCoord3f( +1, +1, -1 );  glVertex3f( -D, -D, +D ); 
        glTexCoord3f( +1, +1, +1 );  glVertex3f( -D, -D, -D ); 
        
    glEnd();
    
    // GL_TEXTURE_CUBE_MAP_POSITIVE_Y
    glBegin(GL_QUADS);
        glTexCoord3f( +1, -1, +1 );  glVertex3f( -D, +D, -D ); 
        glTexCoord3f( +1, -1, -1 );  glVertex3f( -D, +D, +D ); 
        glTexCoord3f( -1, -1, -1 );  glVertex3f( +D, +D, +D ); 
        glTexCoord3f( -1, -1, +1 );  glVertex3f( +D, +D, -D ); 
    glEnd();
    
    // GL_TEXTURE_CUBE_MAP_NEGATIVE_Z
    glBegin(GL_QUADS);
        glTexCoord3f( -1, +1, +1 );  glVertex3f( +D, -D, -D ); 
        glTexCoord3f( +1, +1, +1 );  glVertex3f( -D, -D, -D ); 
        glTexCoord3f( +1, -1, +1 );  glVertex3f( -D, +D, -D ); 
        glTexCoord3f( -1, -1, +1 );  glVertex3f( +D, +D, -D ); 
    glEnd();

    // GL_TEXTURE_CUBE_MAP_POSITIVE_Z
    glBegin(GL_QUADS);
        glTexCoord3f( +1, +1, -1 );  glVertex3f( -D, -D, +D ); 
        glTexCoord3f( -1, +1, -1 );  glVertex3f( +D, -D, +D ); 
        glTexCoord3f( -1, -1, -1 );  glVertex3f( +D, +D, +D ); 
        glTexCoord3f( +1, -1, -1 );  glVertex3f( -D, +D, +D ); 
    glEnd();

    if (g_Renderer.GetRenderPath() == CRenderer::RP_SHADER)
    {
        skytech->EndPass();
    }
    else
    {
        glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
        glDisable(GL_TEXTURE_CUBE_MAP);
        glEnable(GL_TEXTURE_2D);
    }
    
    glPopMatrix();

    glDepthMask( GL_TRUE );

#endif
}