Renderer3D.h

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//
// Copyright 2020 Arvind Singh
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
//version 2.1 of the License, or (at your option) any later version.
//
// This library 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
// Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this library; If not, see <http://www.gnu.org/licenses/>.
 
#ifndef _TGX_RENDERER3D_H_
#define _TGX_RENDERER3D_H_
 
// only C++, no plain C
#ifdef __cplusplus
 
 
#include "Misc.h"
#include "Color.h"
#include "Vec2.h"
#include "Vec3.h"
#include "Vec4.h"
#include "Box2.h"
#include "Box3.h"
#include "Mat4.h"
#include "Image.h"
 
#include "Shaders.h"
#include "Rasterizer.h"
 
#include "Mesh3D.h"
 
 
 
 
 
 
 
 
namespace tgx
{
 
    // forward declaration for the vertices and faces of the unit cube [-1,1]^3 
     
    extern const tgx::fVec3 UNIT_CUBE_VERTICES[8];
    extern const tgx::fVec3 UNIT_CUBE_NORMALS[6];
    extern const uint16_t UNIT_CUBE_FACES[6*4];   
    extern const uint16_t UNIT_CUBE_FACES_NORMALS[6 * 4];
 
 
 
    template<typename color_t, Shader LOADED_SHADERS = TGX_SHADER_MASK_ALL, typename ZBUFFER_t = float>
    class Renderer3D
    {
       
 
        static constexpr int MAXVIEWPORTDIMENSION = 2048 * (1 << ((8 - TGX_RASTERIZE_SUBPIXEL_BITS) >> 1)); 
 
        static_assert(is_color<color_t>::value, "color_t must be one of the color types defined in color.h");
        static_assert((std::is_same<ZBUFFER_t, float>::value) || (std::is_same<ZBUFFER_t, uint16_t>::value), "The Z-buffer type must be either float or uint16_t");
                    
        // true if some kind of texturing may be used. 
        static constexpr int ENABLE_TEXTURING = (TGX_SHADER_HAS_ONE_FLAG(LOADED_SHADERS , (SHADER_TEXTURE | TGX_SHADER_MASK_TEXTURE_MODE | TGX_SHADER_MASK_TEXTURE_QUALITY)));
        
        static constexpr Shader ENABLED_SHADERS = LOADED_SHADERS | (ENABLE_TEXTURING ? SHADER_TEXTURE : SHADER_NOTEXTURE); // enable texturing when at least one texturing related flag is set
        
        // check that disabled shaders do not completely disable all drawing operations.         
        static_assert(TGX_SHADER_HAS_ONE_FLAG(ENABLED_SHADERS,TGX_SHADER_MASK_PROJECTION), "At least one of the two shaders SHADER_PERSPECTIVE or SHADER_ORTHO must be enabled");        
        static_assert(TGX_SHADER_HAS_ONE_FLAG(ENABLED_SHADERS,TGX_SHADER_MASK_ZBUFFER), "At least one of the two shaders SHADER_NOZBUFFER or SHADER_ZBUFFER must be enabled");        
        static_assert(TGX_SHADER_HAS_ONE_FLAG(ENABLED_SHADERS,TGX_SHADER_MASK_SHADING), "At least one of the two shaders SHADER_FLAT or SHADER_GOURAUD must be enabled");        
        static_assert(TGX_SHADER_HAS_ONE_FLAG(ENABLED_SHADERS,TGX_SHADER_MASK_TEXTURE), "At least one of the two shaders SHADER_TEXTURE or SHADER_NOTEXTURE must be enabled");                              
        static_assert((~(TGX_SHADER_HAS_TEXTURE(ENABLED_SHADERS))) || (TGX_SHADER_HAS_ONE_FLAG(ENABLED_SHADERS,TGX_SHADER_MASK_TEXTURE_QUALITY)),"When using texturing, at least one of the two shaders SHADER_TEXTURE_BILINEAR or SHADER_TEXTURE_NEAREST must be enabled");
        static_assert((~(TGX_SHADER_HAS_TEXTURE(ENABLED_SHADERS))) || (TGX_SHADER_HAS_ONE_FLAG(ENABLED_SHADERS, TGX_SHADER_MASK_TEXTURE_MODE)), "When using texturing, at least one of the two shaders SHADER_TEXTURE_WRAP_POW2 or SHADER_TEXTURE_CLAMP must be enabled");
 
 
 
       public:
 
 
        TGX_NOINLINE Renderer3D(const iVec2& viewportSize = {0,0}, Image<color_t> * im = nullptr, ZBUFFER_t * zbuffer = nullptr);
 
 
 
 
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
 
 
        void setViewportSize(int lx, int ly);
 
 
        void setViewportSize(const iVec2& viewport_dim);
 
 
        void setImage(Image<color_t>* im);
 
 
        void setOffset(int ox, int oy);
 
 
        void setOffset(const iVec2& offset);
 
 
        void setProjectionMatrix(const fMat4& M);
 
 
        fMat4 getProjectionMatrix() const;
 
 
        void useOrthographicProjection();
 
 
        void usePerspectiveProjection();
 
 
        void setOrtho(float left, float right, float bottom, float top, float zNear, float zFar);
 
 
        void setFrustum(float left, float right, float bottom, float top, float zNear, float zFar);
 
 
        void setPerspective(float fovy, float aspect, float zNear, float zFar);
 
 
        void setCulling(int w);
 
 
        void setZbuffer(ZBUFFER_t* zbuffer);
 
 
        void clearZbuffer();
 
 
        void setShaders(Shader shaders);
 
 
        void setTextureWrappingMode(Shader wrap_mode);
 
 
        void setTextureQuality(Shader quality);
 
 
 
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
 
 
 
        void setViewMatrix(const fMat4& M);
 
 
        fMat4 getViewMatrix() const;
 
 
        void setLookAt(float eyeX, float eyeY, float eyeZ, float centerX, float centerY, float centerZ, float upX, float upY, float upZ);
 
 
        void setLookAt(const fVec3 eye, const fVec3 center, const fVec3 up);
 
 
        fVec4 worldToNDC(fVec3 P);
 
 
        iVec2 worldToImage(fVec3 P);
 
 
        void setLightDirection(const fVec3& direction);
 
 
        void setLightAmbiant(const RGBf& color);
 
 
        void setLightDiffuse(const RGBf& color);
 
 
        void setLightSpecular(const RGBf& color);
 
 
        void setLight(const fVec3 direction, const RGBf& ambiantColor, const RGBf& diffuseColor, const RGBf& specularColor);
 
 
 
 
        
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
        
       
 
        void setModelMatrix(const fMat4& M);
 
 
        fMat4  getModelMatrix() const;
 
 
        void setModelPosScaleRot(const fVec3& center = fVec3{ 0,0,0 }, const fVec3& scale = fVec3(1, 1, 1), float rot_angle = 0, const fVec3& rot_dir = fVec3{ 0,1,0 });
 
 
        fVec4 modelToNDC(fVec3 P);
 
 
        iVec2 modelToImage(fVec3 P);
 
 
        void setMaterialColor(RGBf color);
 
 
        void setMaterialAmbiantStrength(float strenght = 0.1f);
 
 
        void setMaterialDiffuseStrength(float strenght = 0.6f);
 
 
        void setMaterialSpecularStrength(float strenght = 0.5f);
 
 
        void setMaterialSpecularExponent(int exponent = 16);
 
 
        void setMaterial(RGBf color, float ambiantStrength, float diffuseStrength, float specularStrength, int specularExponent);
 
 
 
 
 
 
 
        
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
 
 
 
        void drawMesh(const Mesh3D<color_t>* mesh, bool use_mesh_material = true, bool draw_chained_meshes = true);
 
 
        void drawTriangle(const fVec3 & P1, const fVec3 & P2, const fVec3 & P3,
                          const fVec3 * N1 = nullptr, const fVec3 * N2 = nullptr, const fVec3 * N3 = nullptr,
                          const fVec2 * T1 = nullptr, const fVec2 * T2 = nullptr, const fVec2 * T3 = nullptr,
                          const Image<color_t> * texture = nullptr);
 
 
        void drawTriangleWithVertexColor(const fVec3 & P1, const fVec3 & P2, const fVec3 & P3,
                                         const RGBf & col1, const RGBf & col2, const RGBf & col3,
                                         const fVec3 * N1 = nullptr, const fVec3 * N2 = nullptr, const fVec3 * N3 = nullptr);
 
 
        void drawTriangles(int nb_triangles,
                           const uint16_t * ind_vertices, const fVec3 * vertices,
                           const uint16_t * ind_normals = nullptr, const fVec3* normals = nullptr,
                           const uint16_t * ind_texture = nullptr, const fVec2* textures = nullptr,
                           const Image<color_t> * texture_image = nullptr);
 
 
 
        void drawQuad(const fVec3 & P1, const fVec3 & P2, const fVec3 & P3, const fVec3 & P4,
                      const fVec3 * N1 = nullptr, const fVec3 * N2 = nullptr, const fVec3 * N3 = nullptr, const fVec3 * N4 = nullptr,
                      const fVec2 * T1 = nullptr, const fVec2 * T2 = nullptr, const fVec2 * T3 = nullptr, const fVec2 * T4 = nullptr,
                      const Image<color_t>* texture = nullptr);
        
 
 
        void drawQuadWithVertexColor(const fVec3 & P1, const fVec3 & P2, const fVec3 & P3, const fVec3 & P4,
                                     const RGBf & col1, const RGBf & col2, const RGBf & col3, const RGBf & col4,
                                     const fVec3 * N1 = nullptr, const fVec3 * N2 = nullptr, const fVec3 * N3 = nullptr, const fVec3 * N4 = nullptr);
         
 
 
 
        void drawQuads(int nb_quads,
                       const uint16_t * ind_vertices, const fVec3 * vertices,
                       const uint16_t * ind_normals = nullptr, const fVec3* normals = nullptr,
                       const uint16_t * ind_texture = nullptr, const fVec2* textures = nullptr,
                       const Image<color_t>* texture_image = nullptr);
 
 
 
 
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
 
 
 
        void drawCube();
            
        
        void drawCube(
            const fVec2 v_front_ABCD[4] , const Image<color_t>* texture_front,
            const fVec2 v_back_EFGH[4]  , const Image<color_t>* texture_back,
            const fVec2 v_top_HADE[4]   , const Image<color_t>* texture_top,
            const fVec2 v_bottom_BGFC[4], const Image<color_t>* texture_bottom,
            const fVec2 v_left_HGBA[4]  , const Image<color_t>* texture_left,
            const fVec2 v_right_DCFE[4] , const Image<color_t>* texture_right
            );
 
 
        void drawCube(
            const Image<color_t>* texture_front,
            const Image<color_t>* texture_back,
            const Image<color_t>* texture_top,
            const Image<color_t>* texture_bottom,
            const Image<color_t>* texture_left,
            const Image<color_t>* texture_right
            );
 
 
 
        void drawSphere(int nb_sectors, int nb_stacks);
 
 
        void drawSphere(int nb_sectors, int nb_stacks, const Image<color_t>* texture);
 
 
        void drawAdaptativeSphere(float quality = 1.0f);
 
 
        void drawAdaptativeSphere(const Image<color_t>* texture, float quality = 1.0f);
 
 
 
 
 
 
 
 
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
 
 
 
        void drawWireFrameMesh(const Mesh3D<color_t>* mesh, bool draw_chained_meshes = true);
 
 
        void drawWireFrameMesh(const Mesh3D<color_t>* mesh, bool draw_chained_meshes, float thickness, color_t color, float opacity);
 
 
        void drawWireFrameLine(const fVec3& P1, const fVec3& P2);
 
 
        void drawWireFrameLine(const fVec3& P1, const fVec3& P2, float thickness, color_t color, float opacity);
 
 
        void drawWireFrameLines(int nb_lines, const uint16_t* ind_vertices, const fVec3* vertices);
 
 
        void drawWireFrameLines(int nb_lines, const uint16_t* ind_vertices, const fVec3* vertices, float thickness, color_t color, float opacity);
 
 
        void drawWireFrameTriangle(const fVec3& P1, const fVec3& P2, const fVec3& P3);
 
 
        void drawWireFrameTriangle(const fVec3& P1, const fVec3& P2, const fVec3& P3, float thickness, color_t color, float opacity);
 
 
        void drawWireFrameTriangles(int nb_triangles, const uint16_t* ind_vertices, const fVec3* vertices);
 
 
        void drawWireFrameTriangles(int nb_triangles, const uint16_t* ind_vertices, const fVec3* vertices, float thickness, color_t color, float opacity);
 
 
        void drawWireFrameQuad(const fVec3& P1, const fVec3& P2, const fVec3& P3, const fVec3& P4);
 
 
        void drawWireFrameQuad(const fVec3& P1, const fVec3& P2, const fVec3& P3, const fVec3& P4, float thickness, color_t color, float opacity);
 
 
        void drawWireFrameQuads(int nb_quads, const uint16_t* ind_vertices, const fVec3* vertices);
 
 
        void drawWireFrameQuads(int nb_quads, const uint16_t* ind_vertices, const fVec3* vertices, float thickness, color_t color, float opacity);
 
 
 
 
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
 
 
        void drawWireFrameCube();
 
 
        void drawWireFrameCube(float thickness, color_t color, float opacity);
 
 
        void drawWireFrameSphere(int nb_sectors, int nb_stacks);
 
 
        void drawWireFrameSphere(int nb_sectors, int nb_stacks, float thickness, color_t color, float opacity);
 
 
        void drawWireFrameAdaptativeSphere(float quality = 1.0f);
 
 
        void drawWireFrameAdaptativeSphere(float quality, float thickness, color_t color, float opacity);
 
 
 
 
 
        /*****************************************************************************************
        *****************************************************************************************/
        /*****************************************************************************************
        ******************************************************************************************/
 
 
 
        void drawPixel(const fVec3& pos);
 
 
        void drawPixel(const fVec3& pos, color_t color, float opacity);
 
 
        void drawPixels(int nb_pixels, const fVec3* pos_list);
 
 
        void drawPixels(int nb_pixels, const fVec3* pos_list, const int* colors_ind, const color_t* colors, const int* opacities_ind, const float* opacities);
 
 
        void drawDot(const fVec3& pos, int r);
 
 
 
        void drawDot(const fVec3& pos, int r, color_t color, float opacity);
 
 
        void drawDots(int nb_dots, const fVec3* pos_list, const int radius);
 
 
        void drawDots(int nb_dots, const fVec3* pos_list, const int* radius_ind, const int* radius, const int* colors_ind, const color_t* colors, const int* opacities_ind, const float* opacities);
 
 
 
 
 
 
 
 
 
 
    private:
 
 
 
        /*****************************************************************************************
        ******************************************************************************************
        *
        * BE CAREFUL PAST THIS POINT... FOR HERE BE DRAGONS !
        *
        ******************************************************************************************
        ******************************************************************************************/
 
 
        TGX_INLINE float _clipbound_xy() const
            { 
            return (256 + 3*((MAXVIEWPORTDIMENSION * 256) / ((_lx > _ly) ? _lx : _ly))) / 1024.0f; // use integer computation up to the last divide
            //return (1.0f + 3.0f * (((float)MAXVIEWPORTDIMENSION) / ((_lx > _ly) ? _lx : _ly))) / 4.0f;                                  
            }
 
 
        TGX_INLINE bool _validDraw() const
            {
            return ((_lx > 0) && (_ly > 0) && (_uni.im != nullptr) && (_uni.im->isValid()));
            }
 
 
        TGX_NOINLINE void _recompute_wa_wb();
 
 
        /***********************************************************
        * Making sure shader flags are coherent
        ************************************************************/
 
        TGX_NOINLINE void _rectifyShaderOrtho();
 
 
        TGX_NOINLINE void _rectifyShaderZbuffer();
 
 
        TGX_NOINLINE void _rectifyShaderShading(Shader new_shaders);
 
 
        TGX_NOINLINE void _rectifyShaderTextureWrapping();
 
 
        TGX_NOINLINE void _rectifyShaderTextureQuality();
       
 
       /***********************************************************
        * DRAWING STUFF
        ************************************************************/
 
 
        void _drawTriangleClipped(const int RASTER_TYPE,
            const fVec4* Q0, const fVec4* Q1, const fVec4* Q2,
            const fVec3* N0, const fVec3* N1, const fVec3* N2,
            const fVec2* T0, const fVec2* T1, const fVec2* T2,
            const RGBf& Vcol0, const RGBf& Vcol1, const RGBf& Vcol2);
 
 
        void _drawTriangleClippedSub(const int RASTER_TYPE, const int plane,
            const RasterizerVec4& P1, const RasterizerVec4& P2, const RasterizerVec4& P3);
 
 
        void _drawTriangle(const int RASTER_TYPE,
            const fVec3* P0, const fVec3* P1, const fVec3* P2,
            const fVec3* N0, const fVec3* N1, const fVec3* N2,
            const fVec2* T0, const fVec2* T1, const fVec2* T2,
            const RGBf& Vcol0, const RGBf& Vcol1, const RGBf& Vcol2);
        
 
        void _drawQuad(const int RASTER_TYPE,
            const fVec3* P0, const fVec3* P1, const fVec3* P2, const fVec3* P3,
            const fVec3* N0, const fVec3* N1, const fVec3* N2, const fVec3* N3,
            const fVec2* T0, const fVec2* T1, const fVec2* T2, const fVec2* T3,
            const RGBf& Vcol0, const RGBf& Vcol1, const RGBf& Vcol2, const RGBf& Vcol3);
 
 
        void _drawMesh(const int RASTER_TYPE, const Mesh3D<color_t>* mesh);
 
 
 
        /***********************************************************
        * Drawing wireframe
        ************************************************************/
 
 
        template<bool DRAW_FAST> void _drawWireFrameMesh(const Mesh3D<color_t>* mesh, bool draw_chained_meshes, color_t color, float opacity, float thickness);
 
        template<bool DRAW_FAST> void _drawWireFrameLine(const fVec3& P1, const fVec3& P2, color_t color, float opacity, float thickness);
 
        template<bool DRAW_FAST> void _drawWireFrameLines(int nb_lines, const uint16_t* ind_vertices, const fVec3* vertices, color_t color, float opacity, float thickness);
 
        template<bool DRAW_FAST> void _drawWireFrameTriangle(const fVec3& P1, const fVec3& P2, const fVec3& P3, color_t color, float opacity, float thickness);
 
        template<bool DRAW_FAST> void _drawWireFrameTriangles(int nb_triangles, const uint16_t* ind_vertices, const fVec3* vertices, color_t color, float opacity, float thickness);
 
        template<bool DRAW_FAST> void _drawWireFrameQuad(const fVec3& P1, const fVec3& P2, const fVec3& P3, const fVec3& P4, color_t color, float opacity, float thickness);
 
        template<bool DRAW_FAST> void _drawWireFrameQuads(int nb_quads, const uint16_t* ind_vertices, const fVec3* vertices, color_t color, float opacity, float thickness);
 
 
 
 
        /***********************************************************
        * Simple geometric objects
        ************************************************************/
        
 
        template<bool USE_BLENDING> void _drawPixel(const fVec3& pos, color_t color, float opacity);
           
 
        template<bool USE_COLORS, bool USE_BLENDING> void _drawPixels(int nb_pixels, const fVec3* pos_list, const int* colors_ind, const color_t* colors, const int* opacities_ind, const float* opacities);
            
 
        template<bool USE_BLENDING> void _drawDot(const fVec3& pos, int r, color_t color, float opacity);
           
 
        template<bool USE_RADIUS, bool USE_COLORS, bool USE_BLENDING> void _drawDots(int nb_dots, const fVec3* pos_list, const int* radius_ind, const int* radius, const int* colors_ind, const color_t* colors, const int* opacities_ind, const float* opacities);
            
 
 
        template<bool CHECKRANGE, bool USE_BLENDING> TGX_INLINE inline void drawPixelZbuf(int x, int y, color_t color, float opacity, float z)
            {
            if (CHECKRANGE && ((x < 0) || (x >= _uni.im->lx()) || (y < 0) || (y >= _uni.im->ly()))) return;           
            ZBUFFER_t& W = _uni.zbuf[x + _uni.im->lx() * y];
            const ZBUFFER_t aa =  (std::is_same<ZBUFFER_t, uint16_t>::value) ? ((ZBUFFER_t)(z * _uni.wa + _uni.wb)) : ((ZBUFFER_t)z);
            if (W < aa)
                {
                W = aa;
                if (USE_BLENDING) _uni.im->template drawPixel<false>({ x, y }, color, opacity); else _uni.im->template drawPixel<false>({ x, y }, color);
                }
            }
 
 
        template<bool CHECKRANGE, bool USE_BLENDING> TGX_INLINE inline void drawHLineZbuf(int x, int y, int w, color_t color, float opacity, float z)
            {
            if (CHECKRANGE) // optimized away at compile time
                {
                const int lx = _uni.im->lx();
                const int ly = _uni.im->ly();
                if ((y < 0) || (y >= ly) || (x >= lx)) return;
                if (x < 0) { w += x; x = 0; }
                if (x + w > lx) { w = lx - x; }
                }
            while(w--) drawPixelZbuf<CHECKRANGE, USE_BLENDING>(x++, y, color, opacity, z);
            }
 
 
        template<bool CHECKRANGE, bool USE_BLENDING> void _drawCircleZbuf(int xm, int ym, int r, color_t color, float opacity, float z);
 
 
        float _unitSphereScreenDiameter();
 
 
        template<bool WIREFRAME, bool DRAWFAST> void _drawSphere(int nb_sectors, int nb_stacks, const Image<color_t>* texture, float thickness, color_t color, float opacity);
 
 
 
        /***********************************************************
        * CLIPPING
        ************************************************************/
 
 
        TGX_INLINE inline void _clip(int & fl, const fVec4 & P, float bx, float Bx, float by, float By)
            {
            if (P.x >= bx) { fl &= (~(1)); }
            if (P.x <= Bx) { fl &= (~(2)); }
            if (P.y >= by) { fl &= (~(4)); }
            if (P.y <= By) { fl &= (~(8)); }
            if ((P.z >= -1.0f)&&(P.w > 0)) { fl &= (~(16)); }
            if (P.z <= +1.0f) { fl &= (~(32)); }
            }
 
 
        TGX_INLINE inline void _clip(int & fl, const fVec3 & P, float bx, float Bx, float by, float By, const fMat4 & M)
            {
            fVec4 S = M.mult1(P);
            if (!_ortho) S.zdivide();
            return _clip(fl, S, bx, Bx, by, By);
            }
 
 
        /* test if a box is outside the image and should be discarded.
           transform the box coords with M then z-divide. */
        bool _discardBox(const fBox3 & bb, const fMat4 & M)
            {
            if ((bb.minX == 0) && (bb.maxX == 0) && (bb.minY == 0) && (bb.maxY == 0) && (bb.minZ == 0) && (bb.maxZ == 0))
                return false; // do not discard if the bounding box is uninitialized.
 
            const float bx = (_ox - 1) * _ilx - 1.0f;
            const float Bx = (_ox + _uni.im->width() + 1) * _ilx - 1.0f;
            const float by = (_oy - 1) * _ily - 1.0f;
            const float By = (_oy + _uni.im->height() + 1) * _ily - 1.0f;
 
            int fl = 63; // every bit set
            _clip(fl, fVec3(bb.minX, bb.minY, bb.minZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            _clip(fl, fVec3(bb.minX, bb.minY, bb.maxZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            _clip(fl, fVec3(bb.minX, bb.maxY, bb.minZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            _clip(fl, fVec3(bb.minX, bb.maxY, bb.maxZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            _clip(fl, fVec3(bb.maxX, bb.minY, bb.minZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            _clip(fl, fVec3(bb.maxX, bb.minY, bb.maxZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            _clip(fl, fVec3(bb.maxX, bb.maxY, bb.minZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            _clip(fl, fVec3(bb.maxX, bb.maxY, bb.maxZ), bx, Bx, by, By, M);
            if (fl == 0) return false;
            return true;
            }
 
 
        /* test if a triangle is completely outside the image and should be discarded.
         * coords are given after z-divide. */
        bool _discardTriangle(const fVec4 & P1, const fVec4 & P2, const fVec4 & P3)
            {
            const float bx = (_ox - 1) * _ilx - 1.0f;
            const float Bx = (_ox + _uni.im->width() + 1) * _ilx - 1.0f;
            const float by = (_oy - 1) * _ily - 1.0f;
            const float By = (_oy + _uni.im->height() + 1) * _ily - 1.0f;
 
            int fl = 63; // every bit set
            _clip(fl, P1, bx, Bx, by, By);
            if (fl == 0) return false;
            _clip(fl, P2, bx, Bx, by, By);
            if (fl == 0) return false;
            _clip(fl, P3, bx, Bx, by, By);
            if (fl == 0) return false;
            return true;
            }
 
 
        bool _clip2(float clipboundXY, const fVec3 & P, const fMat4 & M)
            {
            fVec4 S = M.mult1(P);
            if (!_ortho)
                {
                S.zdivide();
                if (S.w <= 0) S.z = -2;
                }
            return ((S.x <= -clipboundXY) || (S.x >= clipboundXY)
                 || (S.y <= -clipboundXY) || (S.y >= clipboundXY)
                 || (S.z <= -1) || (S.z >= 1));
            }
 
 
        bool _clipTestNeeded(float clipboundXY, const fBox3 & bb, const fMat4 & M)
            {
            return (_clip2(clipboundXY, fVec3(bb.minX, bb.minY, bb.minZ), M)
                 || _clip2(clipboundXY, fVec3(bb.minX, bb.minY, bb.maxZ), M)
                 || _clip2(clipboundXY, fVec3(bb.minX, bb.maxY, bb.minZ), M)
                 || _clip2(clipboundXY, fVec3(bb.minX, bb.maxY, bb.maxZ), M)
                 || _clip2(clipboundXY, fVec3(bb.maxX, bb.minY, bb.minZ), M)
                 || _clip2(clipboundXY, fVec3(bb.maxX, bb.minY, bb.maxZ), M)
                 || _clip2(clipboundXY, fVec3(bb.maxX, bb.maxY, bb.minZ), M)
                 || _clip2(clipboundXY, fVec3(bb.maxX, bb.maxY, bb.maxZ), M));
            }
 
 
 
 
        /***********************************************************
        * TRIANGLE CLIPPING AGAINST A CLIP-PLANE
        ************************************************************/
 
        inline float _cpdist(const tgx::fVec4& CP, float off, const tgx::fVec4& P)
            {
            return (CP.x * P.x) + (CP.y * P.y) + (CP.z * P.z) + (CP.w * P.w) + off;
            }
 
        inline float _cpfactor(const tgx::fVec4& CP, const float sdistA, const float sdistB)
            {
            return sdistA / (sdistA - sdistB);
            }
 
 
        void _triangleClip1in(int shader, tgx::fVec4 CP,
            float cp1, float cp2, float cp3,
            const RasterizerVec4& P1, const RasterizerVec4& P2, const RasterizerVec4& P3,
            RasterizerVec4& nP1, RasterizerVec4& nP2, RasterizerVec4& nP3, RasterizerVec4& nP4);
 
 
        void _triangleClip2in(int shader, tgx::fVec4 CP,
            float cp1, float cp2, float cp3,
            const RasterizerVec4& P1, const RasterizerVec4& P2, const RasterizerVec4& P3,
            RasterizerVec4& nP1, RasterizerVec4& nP2, RasterizerVec4& nP3, RasterizerVec4& nP4);
 
 
        int _triangleClip(int shader, tgx::fVec4 CP, float off,
            const RasterizerVec4 & P1, const RasterizerVec4 & P2, const RasterizerVec4 & P3,
            RasterizerVec4 & nP1, RasterizerVec4 & nP2, RasterizerVec4 & nP3, RasterizerVec4 & nP4);
 
 
 
        /***********************************************************
        * PHONG LIGHTNING
        ************************************************************/
 
        static const int _POWTABSIZE = 32;      // number of entries in the precomputed power table for specular exponent.
        int _currentpow;                        // exponent for the currently computed table (<0 if table not yet computed)
        float _powmax;                          // used to compute exponent
        float _fastpowtab[_POWTABSIZE];         // the precomputed power table.
 
        TGX_INLINE inline void _precomputeSpecularTable(int exponent)
            {
            if (_currentpow == exponent) return;
            _precomputeSpecularTable2(exponent);
            }
 
        TGX_NOINLINE void _precomputeSpecularTable2(int exponent);
 
 
        TGX_INLINE inline float _powSpecular(float x) const
            {
            const float indf = (_powmax - x) * _POWTABSIZE;
            const int indi = max(0,(int)indf);
            return (indi >= (_POWTABSIZE - 1)) ? 0.0f : (_fastpowtab[indi] + (indf - indi) * (_fastpowtab[indi + 1] - _fastpowtab[indi]));;
            }
 
 
        template<bool TEXTURE> TGX_INLINE inline RGBf _phong(float v_diffuse, float v_specular) const
            {
            RGBf col = _r_ambiantColor;
            col += _r_diffuseColor * max(v_diffuse, 0.0f);
            col += _r_specularColor * _powSpecular(v_specular); // pow() this is too slow so we use a lookup table instead
            if (!(TEXTURE)) col *= _r_objectColor;
            col.clamp();
            return col;
            }
 
 
        TGX_INLINE  inline RGBf _phong(float v_diffuse, float v_specular, RGBf color) const
            {
            RGBf col = _r_ambiantColor;
            col += _r_diffuseColor * max(v_diffuse, 0.0f);
            col += _r_specularColor * _powSpecular(v_specular); // pow() this is too slow so we use a lookup table instead
            col *= color;
            col.clamp();
            return col;
            }
 
 
 
        /***********************************************************
        * MEMBER VARIABLES
        ************************************************************/
 
        // *** general parameters ***
 
        int     _lx, _ly;           // viewport dimension        
        float   _ilx, _ily;         // inverse viewport dimension
 
        int     _ox, _oy;           // image offset w.r.t. the viewport        
 
        bool    _ortho;             // true to use orthographic projection and false for perspective projection
        
        fMat4   _projM;             // projection matrix
 
        RasterizerParams<color_t, color_t,ZBUFFER_t>  _uni; // rasterizer param (contain the image pointer and the zbuffer pointer).
 
        float _culling_dir;         // culling direction postive/negative or 0 to disable back face culling.
 
        int   _shaders;             // the shaders to use. 
        int   _texture_wrap_mode;   // wrapping mode (wrap_pow2 or clamp)
        int   _texture_quality;     // texturing quality (nearest or bilinear)
 
        // *** scene parameters ***
 
        fMat4   _viewM;             // view transform matrix
 
        fVec3   _light;             // light direction
        RGBf    _ambiantColor;      // light ambiant color
        RGBf    _diffuseColor;      // light diffuse color
        RGBf    _specularColor;     // light specular color
 
 
        // *** model specific parameters ***
 
        fMat4   _modelM;            // model transform matrix
 
        RGBf    _color;             // model color (use when texturing is disabled)
        float   _ambiantStrength;   // ambient light reflection strength
        float   _diffuseStrength;   // diffuse light reflection strength
        float   _specularStrength;  // specular light reflection strength
        int     _specularExponent;  // specular exponent
 
 
        // *** pre-computed values ***
        fMat4 _r_modelViewM;        // model-view matrix
        float _r_inorm;             // inverse of the norm of a unit vector after view transform
        fVec3 _r_light;             // light vector in view space (inverted and normalized)
        fVec3 _r_light_inorm;       // same as above but alreadsy muliplied by inorm
        fVec3 _r_H;                 // halfway vector.
        fVec3 _r_H_inorm;           // same as above but already muliplied by inorm
        RGBf _r_ambiantColor;       // ambient color multipled by object ambient strenght
        RGBf _r_diffuseColor;       // diffuse color multipled by object diffuse strenght
        RGBf _r_specularColor;      // specular color multipled by object specular strenght
        RGBf _r_objectColor;        // color to use for drawing the object (either _color or mesh->color).
 
 
        struct ExtVec4 : public RasterizerVec4
            {
            fVec4 P;       // after model-view matrix multiplication
            fVec4 N;       // normal vector after model-view matrix multiplication
            bool missedP;  // true if the attributes should be computed
            int indn;      // index for normal vector in array
            int indt;      // index for texture vector in array
            };
 
 
    };
 
 
 
}
 
 
 
 
#include "Renderer3D.inl"
 
 
#endif
 
#endif