source/renderer/TerrainRenderer.h

   1 /* Copyright (C) 2021 Wildfire Games.
   2  * This file is part of 0 A.D.
   3  *
   4  * 0 A.D. is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * 0 A.D. is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * Terrain rendering (everything related to patches and water) is
  20  * encapsulated in TerrainRenderer
  21  */
  22
  23 #ifndef INCLUDED_TERRAINRENDERER
  24 #define INCLUDED_TERRAINRENDERER
  25
  26 #include "graphics/Color.h"
  27 #include "maths/BoundingBoxAligned.h"
  28
  29 class CCamera;
  30 class CMatrix3D;
  31 class CModelDecal;
  32 class CPatch;
  33 class CShaderDefines;
  34 class CSimulation2;
  35
  36 class ShadowMap;
  37
  38 struct TerrainRendererInternals;
  39
  40 /**
  41  * Class TerrainRenderer: Render everything related to the terrain,
  42  * especially patches and water.
  43  */
  44 class TerrainRenderer
  45 {
  46         friend class CPatchRData;
  47         friend class CDecalRData;
  48
  49 public:
  50         TerrainRenderer();
  51         ~TerrainRenderer();
  52
  53         /**
  54          * Set the simulation context for this frame.
  55          * Call at start of frame, before any other Submits.
  56          */
  57         void SetSimulation(CSimulation2* simulation);
  58
  59         /**
  60          * Submit: Add a patch for rendering in this frame.
  61          *
  62          * preconditions  : PrepareForRendering must not have been called
  63          * for this frame yet.
  64          * The patch must not have been submitted in this frame yet (i.e. you
  65          * can only submit a frame once).
  66          *
  67          * @param patch the patch
  68          */
  69         void Submit(int cullGroup, CPatch* patch);
  70
  71         /**
  72          * Submit: Add a terrain decal for rendering in this frame.
  73          */
  74         void Submit(int cullGroup, CModelDecal* decal);
  75
  76         /**
  77          * PrepareForRendering: Prepare internal data structures like vertex
  78          * buffers for rendering.
  79          *
  80          * All patches must have been submitted before the call to
  81          * PrepareForRendering.
  82          * PrepareForRendering must be called before any rendering calls.
  83          */
  84         void PrepareForRendering();
  85
  86         /**
  87          * EndFrame: Remove all patches from the list of submitted patches.
  88          */
  89         void EndFrame();
  90
  91         /**
  92          * Render textured terrain (including blends between
  93          * different terrain types).
  94          *
  95          * preconditions  : PrepareForRendering must have been called this
  96          * frame before calling RenderTerrain.
  97          *
  98          * @param shadow A prepared shadow map, in case rendering with shadows is enabled.
  99          */
 100         void RenderTerrainShader(const CShaderDefines& context, int cullGroup, ShadowMap* shadow);
 101
 102         /**
 103          * RenderPatches: Render all patches un-textured as polygons.
 104          *
 105          * preconditions  : PrepareForRendering must have been called this
 106          * frame before calling RenderPatches.
 107          *
 108          * @param filtered If true then only render objects that passed CullPatches.
 109          * @param color Fill color of the patches.
 110          */
 111         void RenderPatches(int cullGroup, const CColor& color = CColor(0.0f, 0.0f, 0.0f, 1.0f));
 112
 113         /**
 114          * RenderOutlines: Render the outline of patches as lines.
 115          *
 116          * preconditions  : PrepareForRendering must have been called this
 117          * frame before calling RenderOutlines.
 118          *
 119          * @param filtered If true then only render objects that passed CullPatches.
 120          */
 121         void RenderOutlines(int cullGroup);
 122
 123         /**
 124          * RenderWater: Render water for all patches that have been submitted
 125          * this frame.
 126          *
 127          * preconditions  : PrepareForRendering must have been called this
 128          * frame before calling RenderWater.
 129          */
 130         void RenderWater(const CShaderDefines& context, int cullGroup, ShadowMap* shadow);
 131
 132         /**
 133          * Calculate a scissor rectangle for the visible water patches.
 134          */
 135         CBoundingBoxAligned ScissorWater(int cullGroup, const CCamera& camera);
 136
 137         /**
 138          * Render priority text for all submitted patches, for debugging.
 139          */
 140         void RenderPriorities(int cullGroup);
 141
 142         /**
 143          * Render texture unit 0 over the terrain mesh, with UV coords calculated
 144          * by the given texture matrix.
 145          * Intended for use by TerrainTextureOverlay.
 146          */
 147         void RenderTerrainOverlayTexture(int cullGroup, CMatrix3D& textureMatrix, GLuint texture);
 148
 149 private:
 150         TerrainRendererInternals* m;
 151
 152         /**
 153          * RenderFancyWater: internal rendering method for fancy water.
 154          * Returns false if unable to render with fancy water.
 155          */
 156         bool RenderFancyWater(const CShaderDefines& context, int cullGroup, ShadowMap* shadow);
 157
 158         /**
 159          * RenderSimpleWater: internal rendering method for water
 160          */
 161         void RenderSimpleWater(int cullGroup);
 162
 163         static void PrepareShader(const CShaderProgramPtr& shader, ShadowMap* shadow);
 164 };
 165
 166 #endif // INCLUDED_TERRAINRENDERER