source/renderer/RenderModifiers.h

   1 /* Copyright (C) 2012 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  * RenderModifiers can affect the fragment stage behaviour of some
  20  * ModelRenderers. This file defines some common RenderModifiers in
  21  * addition to the base class.
  22  *
  23  * TODO: See comment in CRendererInternals::Models - we no longer use multiple
  24  * subclasses of RenderModifier, so most of the stuff here is unnecessary
  25  * abstraction which should probably be cleaned up.
  26  */
  27
  28 #ifndef INCLUDED_RENDERMODIFIERS
  29 #define INCLUDED_RENDERMODIFIERS
  30
  31 #include "ModelRenderer.h"
  32 #include "graphics/ShaderProgram.h"
  33 #include "graphics/ShaderTechnique.h"
  34 #include "graphics/Texture.h"
  35
  36 class CLightEnv;
  37 class CMatrix3D;
  38 class CModel;
  39 class ShadowMap;
  40
  41 /**
  42  * Class RenderModifier: Some ModelRenderer implementations provide vertex
  43  * management behaviour but allow fragment stages to be modified by a plugged in
  44  * RenderModifier.
  45  *
  46  * You should use RenderModifierPtr when referencing RenderModifiers.
  47  */
  48 class RenderModifier
  49 {
  50 public:
  51         RenderModifier() { }
  52         virtual ~RenderModifier() { }
  53
  54         /**
  55          * BeginPass: Setup OpenGL for the given rendering pass.
  56          *
  57          * Must be implemented by derived classes.
  58          *
  59          * @param pass The current pass number (pass == 0 is the first pass)
  60          *
  61          * @return The streamflags that indicate which vertex components
  62          * are required by the fragment stages (see STREAM_XYZ constants).
  63          */
  64         virtual void BeginPass(const CShaderProgramPtr& shader) = 0;
  65
  66         /**
  67          * PrepareModel: Called before rendering the given model.
  68          *
  69          * Default behaviour does nothing.
  70          *
  71          * @param pass The current pass number (pass == 0 is the first pass)
  72          * @param model The model that is about to be rendered.
  73          */
  74         virtual void PrepareModel(const CShaderProgramPtr& shader, CModel* model) = 0;
  75 };
  76
  77
  78 /**
  79  * Class LitRenderModifier: Abstract base class for RenderModifiers that apply
  80  * a shadow map.
  81  * LitRenderModifiers expect the diffuse brightness in the primary color (instead of ambient + diffuse).
  82  */
  83 class LitRenderModifier : public RenderModifier
  84 {
  85 public:
  86         LitRenderModifier();
  87         ~LitRenderModifier();
  88
  89         /**
  90          * SetShadowMap: Set the shadow map that will be used for rendering.
  91          * Must be called by the user of the RenderModifier.
  92          *
  93          * The shadow map must be non-null and use depth texturing, or subsequent rendering
  94          * using this RenderModifier will fail.
  95          *
  96          * @param shadow the shadow map
  97          */
  98         void SetShadowMap(const ShadowMap* shadow);
  99
 100         /**
 101          * SetLightEnv: Set the light environment that will be used for rendering.
 102          * Must be called by the user of the RenderModifier.
 103          *
 104          * @param lightenv the light environment (must be non-null)
 105          */
 106         void SetLightEnv(const CLightEnv* lightenv);
 107
 108         const ShadowMap* GetShadowMap() const { return m_Shadow; }
 109         const CLightEnv* GetLightEnv() const { return m_LightEnv; }
 110
 111 private:
 112         const ShadowMap* m_Shadow;
 113         const CLightEnv* m_LightEnv;
 114 };
 115
 116 /**
 117  * A RenderModifier that sets uniforms and textures appropriately for rendering models.
 118  */
 119 class ShaderRenderModifier : public LitRenderModifier
 120 {
 121 public:
 122         ShaderRenderModifier();
 123
 124         // Implementation
 125         void BeginPass(const CShaderProgramPtr& shader);
 126         void PrepareModel(const CShaderProgramPtr& shader, CModel* model);
 127
 128 private:
 129         CShaderProgram::Binding m_BindingInstancingTransform;
 130         CShaderProgram::Binding m_BindingShadingColor;
 131         CShaderProgram::Binding m_BindingPlayerColor;
 132 };
 133
 134 #endif // INCLUDED_RENDERMODIFIERS