[2642] | 1 | #include "Geometry.h"
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| 2 | #include "glInterface.h"
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| 3 | #include "stdio.h"
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| 4 | #include "teapot.h"
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| 5 |
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| 6 | #include <math.h>
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| 7 |
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| 8 | #define NO_LIST -1
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| 9 | #define STRIP_END -1
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| 10 |
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| 11 | int Geometry::num_torus_indices;
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| 12 | int Geometry::num_torus_vertices;
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| 13 | int Geometry::num_torus_normals;
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| 14 |
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| 15 | const int Geometry::torus_precision = 24;
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| 16 | const int Geometry::sphere_precision = 24;
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| 17 |
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| 18 | float *Geometry::torus_vertices;
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| 19 | float *Geometry::torus_normals;
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| 20 | int *Geometry::torus_indices;
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| 21 |
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| 22 | // choose size so the glut-rendered sphere is approximately
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| 23 | // as big as the other objects
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| 24 | const float Geometry::sphere_radius = 1.0 / 9.0f;
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| 25 | const float Geometry::torus_inner_radius = 0.05;
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| 26 | const float Geometry::torus_outer_radius = 0.07;
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| 27 |
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| 28 | int Geometry::sDisplayList[NUM_OBJECTS];
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| 29 |
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| 30 | bool Geometry::sIsInitialised = Init();
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| 31 |
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| 32 | Geometry::Geometry():
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| 33 | mXRotation(0), mYRotation(0), mZRotation(0), mScale(1.0), mObjectType(TEAPOT)
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| 34 | {
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| 35 | copyVector3Values(mTranslation, 0, 0, 0);
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| 36 |
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| 37 | SetAmbientColor(0.1745, 0.01175, 0.01175);
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| 38 | SetDiffuseColor(0.61424, 0.04136, 0.04136);
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| 39 | SetSpecularColor(0.727811, 0.626959, 0.626959);
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| 40 |
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| 41 | CalcBoundingVolume();
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| 42 | CalcTransform();
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| 43 | GenerateList();
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| 44 | }
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| 45 |
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| 46 | Geometry::Geometry(Vector3 translation, float xRot, float yRot, float zRot, float scale, int objectType):
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| 47 | mXRotation(xRot), mYRotation(yRot), mZRotation(zRot), mScale(scale), mObjectType(objectType)
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| 48 | {
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| 49 | copyVector3(mTranslation, translation);
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| 50 |
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| 51 | SetAmbientColor(0.1745, 0.01175, 0.01175);
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| 52 | SetDiffuseColor(0.61424, 0.04136, 0.04136);
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| 53 | SetSpecularColor(0.727811, 0.626959, 0.626959);
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| 54 |
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| 55 | CalcBoundingVolume();
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| 56 | CalcTransform();
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| 57 | GenerateList();
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| 58 | }
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| 59 |
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| 60 | void Geometry::ResetLists()
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| 61 | {
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| 62 | for(int i = 0; i < NUM_OBJECTS; i++)
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| 63 | {
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| 64 | if(sDisplayList[i] == NO_LIST)
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| 65 | glDeleteLists(sDisplayList[i], 1);
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| 66 |
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| 67 | sDisplayList[i] = NO_LIST;
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| 68 | }
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| 69 | }
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| 70 |
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| 71 | void Geometry::CleanUp()
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| 72 | {
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| 73 | ResetLists();
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| 74 |
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| 75 | delete [] torus_vertices;
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| 76 | delete [] torus_normals;
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| 77 | delete [] torus_indices;
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| 78 | }
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| 79 |
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| 80 |
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| 81 | bool Geometry::Init()
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| 82 | {
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| 83 | for(int i=0; i < NUM_OBJECTS; i++)
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| 84 | sDisplayList[i] = NO_LIST;
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| 85 |
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| 86 | // parameters chosen so torus is approximately as big as teapot
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| 87 | CreateTorus(torus_inner_radius, torus_outer_radius, torus_precision);
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| 88 |
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| 89 | return true;
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| 90 | }
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| 91 |
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| 92 | void Geometry::GenerateList()
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| 93 | {
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| 94 | if(sDisplayList[mObjectType] == NO_LIST)
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| 95 | {
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| 96 | sDisplayList[mObjectType] = glGenLists(1);
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| 97 | glNewList(sDisplayList[mObjectType], GL_COMPILE);
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| 98 |
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| 99 | switch(mObjectType)
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| 100 | {
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| 101 | case TEAPOT:
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| 102 | RenderTeapot();
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| 103 | break;
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| 104 | case TORUS:
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| 105 | RenderTorus();
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| 106 | break;
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| 107 | case SPHERE:
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| 108 | RenderSphere();
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| 109 | break;
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| 110 |
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| 111 | default:
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| 112 | break;
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| 113 | }
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| 114 | glEndList();
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| 115 | }
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| 116 | }
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| 117 |
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| 118 | void Geometry::Render()
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| 119 | {
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| 120 | glMaterialfv(GL_FRONT, GL_AMBIENT, mAmbientColor);
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| 121 | glMaterialfv(GL_FRONT, GL_DIFFUSE, mDiffuseColor);
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| 122 | glMaterialfv(GL_FRONT, GL_SPECULAR, mSpecularColor);
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| 123 |
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| 124 | glPushMatrix();
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| 125 |
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| 126 | Transform();
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| 127 |
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| 128 | glCallList(sDisplayList[mObjectType]);
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| 129 |
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| 130 | glPopMatrix();
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| 131 | }
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| 132 |
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| 133 |
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| 134 | //! sets rotations around the three axis: executed in the order specified here
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| 135 | void Geometry::SetRotations(float xRot, float yRot, float zRot)
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| 136 | {
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| 137 | mXRotation = xRot;
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| 138 | mYRotation = yRot;
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| 139 | mZRotation = zRot;
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| 140 |
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| 141 | CalcBoundingVolume();
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| 142 | CalcTransform();
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| 143 | }
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| 144 |
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| 145 |
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| 146 | void Geometry::SetTranslation(Vector3 translation)
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| 147 | {
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| 148 | copyVector3(mTranslation, translation);
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| 149 |
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| 150 | CalcBoundingVolume();
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| 151 | CalcTransform();
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| 152 | }
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| 153 |
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| 154 |
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| 155 | void Geometry::SetScale(float scale)
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| 156 | {
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| 157 | mScale = scale;
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| 158 | CalcTransform();
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| 159 |
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| 160 | CalcBoundingVolume();
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| 161 | }
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| 162 |
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| 163 |
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| 164 | void Geometry::SetAmbientColor(float ambientR, float ambientG, float ambientB)
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| 165 | {
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| 166 | mAmbientColor[0] = ambientR;
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| 167 | mAmbientColor[1] = ambientG;
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| 168 | mAmbientColor[2] = ambientB;
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| 169 | }
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| 170 |
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| 171 |
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| 172 | void Geometry::SetDiffuseColor(float diffuseR, float diffuseG, float diffuseB)
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| 173 | {
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| 174 | mDiffuseColor[0] = diffuseR;
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| 175 | mDiffuseColor[1] = diffuseG;
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| 176 | mDiffuseColor[2] = diffuseB;
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| 177 | }
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| 178 |
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| 179 |
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| 180 | void Geometry::SetSpecularColor(float specularR, float specularG, float specularB)
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| 181 | {
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| 182 | mSpecularColor[0] = specularR;
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| 183 | mSpecularColor[1] = specularG;
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| 184 | mSpecularColor[2] = specularB;
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| 185 | }
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| 186 |
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| 187 |
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| 188 | float Geometry::GetScale()
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| 189 | {
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| 190 | return mScale;
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| 191 | }
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| 192 |
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| 193 |
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| 194 | void Geometry::GetTranslation(Vector3 translation)
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| 195 | {
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| 196 | copyVector3(translation, mTranslation);
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| 197 | }
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| 198 |
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| 199 |
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| 200 | void Geometry::GetRotations(float &xRot, float &yRot, float &zRot)
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| 201 | {
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| 202 | xRot = mXRotation;
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| 203 | yRot = mYRotation;
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| 204 | zRot = mZRotation;
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| 205 | }
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| 206 |
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| 207 |
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| 208 | const AABox &Geometry::GetBoundingVolume()
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| 209 | {
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| 210 | return mBoundingBox;
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| 211 | }
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| 212 |
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| 213 |
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| 214 | void Geometry::SetLastVisited(int lastVisited)
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| 215 | {
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| 216 | mLastVisited = lastVisited;
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| 217 | }
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| 218 |
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| 219 |
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| 220 | int Geometry::GetLastVisited()
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| 221 | {
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| 222 | return mLastVisited;
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| 223 | }
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| 224 |
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| 225 |
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| 226 | void Geometry::SetObjectType(int type)
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| 227 | {
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| 228 | mObjectType = type;
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| 229 | GenerateList();
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| 230 | }
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| 231 |
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| 232 |
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| 233 | void Geometry::RenderTeapot()
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| 234 | {
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| 235 | int i = 0;
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| 236 |
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| 237 | while(i < num_teapot_indices)
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| 238 | {
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| 239 | glBegin(GL_TRIANGLE_STRIP);
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| 240 | while(teapot_indices[i] != STRIP_END)
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| 241 | {
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| 242 | int index = teapot_indices[i] * 3;
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| 243 |
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| 244 | glNormal3fv(teapot_normals + index);
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| 245 | glVertex3fv(teapot_vertices + index);
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| 246 |
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| 247 | i++;
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| 248 | }
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| 249 | glEnd();
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| 250 |
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| 251 | i++; // skip strip end flag
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| 252 | }
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| 253 | }
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| 254 |
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| 255 | void Geometry::CalcBoundingVolume()
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| 256 | {
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| 257 | switch(mObjectType)
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| 258 | {
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| 259 | case TORUS:
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| 260 | CalcBoundingVolume(torus_vertices, num_torus_vertices);
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| 261 | break;
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| 262 | case SPHERE:
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| 263 | CalcSphereBoundingVolume();
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| 264 | break;
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| 265 | case TEAPOT:
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| 266 | CalcBoundingVolume(teapot_vertices, num_teapot_vertices);
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| 267 | break;
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| 268 | default:
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| 269 | break;
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| 270 | }
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| 271 | }
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| 272 |
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| 273 |
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| 274 | void Geometry::CalcBoundingVolume(float *vertices, const int num_vertices)
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| 275 | {
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| 276 | Vector3 *rotatedPoints = new Vector3[num_vertices];
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| 277 |
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| 278 | for(int i = 0; i < num_vertices; i++)
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| 279 | {
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| 280 | copyVector3Values(rotatedPoints[i], vertices[i * 3],
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| 281 | vertices[i * 3 + 1], vertices[i * 3 + 2]);
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| 282 |
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| 283 | rotateVectorZ(rotatedPoints[i], mZRotation * PI_180);
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| 284 | rotateVectorY(rotatedPoints[i], mYRotation * PI_180);
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| 285 | rotateVectorX(rotatedPoints[i], mXRotation * PI_180);
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| 286 | }
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| 287 |
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| 288 | calcCubicHull(mBoundingBox.min, mBoundingBox.max, rotatedPoints, num_vertices);
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| 289 |
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| 290 | for(int i=0; i< 3; i++)
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| 291 | {
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| 292 | mBoundingBox.min[i] *= mScale;
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| 293 | mBoundingBox.max[i] *= mScale;
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| 294 | }
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| 295 |
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| 296 | addVector3(mBoundingBox.min, mTranslation, mBoundingBox.min);
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| 297 | addVector3(mBoundingBox.max, mTranslation, mBoundingBox.max);
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| 298 |
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| 299 | delete [] rotatedPoints;
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| 300 | }
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| 301 |
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| 302 |
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| 303 | void Geometry::CalcSphereBoundingVolume()
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| 304 | {
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| 305 | float len = mScale * sphere_radius;
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| 306 | Vector3 size = {len, len, len};
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| 307 |
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| 308 | diffVector3(mBoundingBox.min, mTranslation, size);
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| 309 | addVector3(mBoundingBox.max, mTranslation, size);
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| 310 | }
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| 311 |
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| 312 |
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| 313 | void Geometry::RenderTorus()
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| 314 | {
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| 315 | glVertexPointer(3, GL_FLOAT, sizeof(float), torus_vertices);
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| 316 | glEnableClientState(GL_VERTEX_ARRAY);
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| 317 |
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| 318 | glNormalPointer(GL_FLOAT, sizeof(float), torus_normals);
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| 319 | glEnableClientState(GL_NORMAL_ARRAY);
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| 320 |
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| 321 | glDrawElements(GL_TRIANGLES, num_torus_indices, GL_UNSIGNED_INT, torus_indices);
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| 322 |
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| 323 | glDisableClientState(GL_VERTEX_ARRAY);
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| 324 | glDisableClientState(GL_NORMAL_ARRAY);
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| 325 | }
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| 326 |
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| 327 | /*
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| 328 | creates a torus with specified radii, with number of rings and ring
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| 329 | subdivision = precision.
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| 330 | */
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| 331 | void Geometry::CreateTorus(float innerRadius, float outerRadius, int precision)
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| 332 | {
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| 333 | num_torus_vertices = num_torus_normals = (precision + 1) * (precision + 1);
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| 334 | num_torus_indices = 2 * precision * precision * 3;
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| 335 |
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| 336 | torus_vertices = new float[num_torus_vertices * 3];
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| 337 | torus_normals = new float[num_torus_normals * 3];
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| 338 | torus_indices = new int[num_torus_indices];
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| 339 |
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| 340 | for(int i = 0; i < precision + 1; ++ i)
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| 341 | {
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| 342 | int index = i * 3;
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| 343 |
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| 344 | Vector3 currentVertex = {innerRadius, 0.0f, 0.0f};
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| 345 | rotateVectorZ(currentVertex, ((float)i * 2.0 * PI) / (float)precision);
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| 346 |
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| 347 | currentVertex[0] += outerRadius;
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| 348 |
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| 349 | Vector3 sTangent = {0.0f, 0.0f, -1.0f};
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| 350 | Vector3 tTangent = {0, -1, 0};
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| 351 | rotateVectorZ(tTangent, ((float)i * 2.0 * PI) / (float)precision);
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| 352 |
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| 353 | Vector3 currentNormal;
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| 354 |
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| 355 | cross(currentNormal, tTangent, sTangent);
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| 356 |
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| 357 | torus_normals[index + 0] = currentNormal[0];
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| 358 | torus_normals[index + 1] = currentNormal[1];
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| 359 | torus_normals[index + 2] = currentNormal[2];
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| 360 |
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| 361 | torus_vertices[index + 0] = currentVertex[0];
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| 362 | torus_vertices[index + 1] = currentVertex[1];
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| 363 | torus_vertices[index + 2] = currentVertex[2];
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| 364 | }
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| 365 |
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| 366 | for(int i_rng = 1; i_rng < precision + 1; ++ i_rng)
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| 367 | {
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| 368 | for(int i=0; i<precision+1; ++i)
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| 369 | {
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| 370 | int index = 3 * (i_rng * (precision + 1) + i);
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| 371 |
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| 372 | Vector3 currentVertex = {torus_vertices[i*3], torus_vertices[i*3+1], torus_vertices[i*3+2]};
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| 373 |
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| 374 | rotateVectorY(currentVertex, ((float)i_rng * 2.0 * PI) / (float)precision);
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| 375 |
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| 376 | Vector3 currentNormal = {torus_normals[i*3], torus_normals[i*3+1], torus_normals[i*3+2]};
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| 377 |
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| 378 | rotateVectorY(currentNormal, ((float)i_rng * 2.0 * PI) / (float)precision);
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| 379 |
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| 380 | torus_normals[index + 0] = currentNormal[0];
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| 381 | torus_normals[index + 1] = currentNormal[1];
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| 382 | torus_normals[index + 2] = currentNormal[2];
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| 383 |
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| 384 | torus_vertices[index + 0] = currentVertex[0];
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| 385 | torus_vertices[index + 1] = currentVertex[1];
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| 386 | torus_vertices[index + 2] = currentVertex[2];
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| 387 | }
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| 388 | }
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| 389 |
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| 390 | for(int i_rng = 0; i_rng < precision; ++ i_rng)
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| 391 | {
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| 392 | for(int i = 0; i < precision; ++ i)
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| 393 | {
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| 394 | int index = ((i_rng * precision + i) * 2) * 3;
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| 395 |
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| 396 | torus_indices[index+0] = (i_rng * (precision+1) + i)*3;
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| 397 | torus_indices[index+1] = ((i_rng+1) * (precision+1) + i)*3;
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| 398 | torus_indices[index+2] = (i_rng * (precision+1) + i + 1)*3;
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| 399 |
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| 400 | index = ((i_rng * precision + i) * 2 + 1) * 3;
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| 401 |
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| 402 | torus_indices[index+0] = (i_rng * (precision+1) + i + 1)*3;
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| 403 | torus_indices[index+1] = ((i_rng+1) * (precision+1) + i)*3;
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| 404 | torus_indices[index+2] = ((i_rng+1) * (precision+1) + i + 1)*3;
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| 405 | }
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| 406 | }
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| 407 | }
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| 408 |
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| 409 | /**
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| 410 | counts the triangles of the teapot.
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| 411 | traverses through all the triangle strips.
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| 412 | */
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| 413 | int Geometry::CountTeapotTriangles()
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| 414 | {
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| 415 | int result = 0;
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| 416 | int i=0;
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| 417 | // n - 2 triangles are drawn for a strip
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| 418 | while(i < num_teapot_indices)
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| 419 | {
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| 420 | while(teapot_indices[i] != STRIP_END)
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| 421 | {
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| 422 | result ++;;
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| 423 | i++;
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| 424 | }
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| 425 | result -= 2;
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| 426 | i++; // skip STRIP_END
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| 427 | }
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| 428 | return result;
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| 429 | }
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| 430 |
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| 431 | /**
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| 432 | counts the triangles of the torus
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| 433 | */
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| 434 | int Geometry::CountTorusTriangles()
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| 435 | {
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| 436 | // every 3 indices specify one triangle
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| 437 | return num_torus_indices / 3;
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| 438 | }
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| 439 |
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| 440 | /**
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| 441 | counts the triangles of the sphere.
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| 442 | sphere_precision / 2 + 1 strips with sphere_precision * 2 - 2 triangles each
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| 443 | */
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| 444 | int Geometry::CountSphereTriangles()
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| 445 | {
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| 446 | return sphere_precision * sphere_precision;
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| 447 | }
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| 448 |
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| 449 |
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| 450 | int Geometry::CountTriangles(int objectType)
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| 451 | {
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| 452 | int result = 0;
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| 453 |
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| 454 | switch(objectType)
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| 455 | {
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| 456 | case TEAPOT:
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| 457 | result = CountTeapotTriangles();
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| 458 | break;
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| 459 | case TORUS:
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| 460 | result = CountTorusTriangles();
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| 461 | break;
|
---|
| 462 | case SPHERE:
|
---|
| 463 | result = CountSphereTriangles();
|
---|
| 464 | break;
|
---|
| 465 | default:
|
---|
| 466 | break;
|
---|
| 467 | }
|
---|
| 468 | return result;
|
---|
| 469 | }
|
---|
| 470 |
|
---|
| 471 |
|
---|
| 472 | void Geometry::Transform()
|
---|
| 473 | {
|
---|
| 474 | glMultMatrixd(mTransform);
|
---|
| 475 | }
|
---|
| 476 |
|
---|
| 477 | void Geometry::CalcTransform()
|
---|
| 478 | {
|
---|
| 479 | Matrix4x4 scale;
|
---|
| 480 | Matrix4x4 xrot;
|
---|
| 481 | Matrix4x4 yrot;
|
---|
| 482 | Matrix4x4 zrot;
|
---|
| 483 | Matrix4x4 transl;
|
---|
| 484 |
|
---|
| 485 | makeScaleMtx(scale, mScale, mScale, mScale);
|
---|
| 486 | makeTranslationMtx(transl, mTranslation);
|
---|
| 487 | makeRotationXMtx(xrot, mXRotation * PI_180);
|
---|
| 488 | makeRotationYMtx(yrot, mYRotation * PI_180);
|
---|
| 489 | makeRotationZMtx(zrot, mZRotation * PI_180);
|
---|
| 490 |
|
---|
| 491 | copyMatrix(mTransform, IDENTITY);
|
---|
| 492 | mult(mTransform, mTransform, transl);
|
---|
| 493 | mult(mTransform, mTransform, xrot);
|
---|
| 494 | mult(mTransform, mTransform, yrot);
|
---|
| 495 | mult(mTransform, mTransform, zrot);
|
---|
| 496 | mult(mTransform, mTransform, scale);
|
---|
| 497 | }
|
---|
| 498 |
|
---|
| 499 | /**
|
---|
| 500 | renders a sphere with sphere_precision subdivisions.
|
---|
| 501 | note: works only for even sphere_precision
|
---|
| 502 | */
|
---|
| 503 | void Geometry::RenderSphere()
|
---|
| 504 | {
|
---|
| 505 | Vector3 vertex;
|
---|
| 506 |
|
---|
| 507 | // this algorithm renders the triangles clockwise
|
---|
| 508 | glFrontFace(GL_CW);
|
---|
| 509 |
|
---|
| 510 | for (int j = 0; j < sphere_precision/2; ++j)
|
---|
| 511 | {
|
---|
| 512 | double alpha = j * PI * 2.0 / (double)sphere_precision - PI_2;
|
---|
| 513 | double beta = (j + 1) * PI * 2.0 / (double)sphere_precision - PI_2;
|
---|
| 514 |
|
---|
| 515 | glBegin(GL_TRIANGLE_STRIP);
|
---|
| 516 |
|
---|
| 517 | for (int i = 0; i <= sphere_precision; ++i)
|
---|
| 518 | {
|
---|
| 519 | double gamma = i * PI * 2.0 / (double)sphere_precision;
|
---|
| 520 |
|
---|
| 521 | vertex[0] = sphere_radius * cos(beta) * cos(gamma);
|
---|
| 522 | vertex[1] = sphere_radius * sin(beta);
|
---|
| 523 | vertex[2] = sphere_radius * cos(beta) * sin(gamma);
|
---|
| 524 |
|
---|
| 525 | glNormal3dv(vertex);
|
---|
| 526 | glVertex3dv(vertex);
|
---|
| 527 |
|
---|
| 528 | vertex[0] = sphere_radius * cos(alpha) * cos(gamma);
|
---|
| 529 | vertex[1] = sphere_radius * sin(alpha);
|
---|
| 530 | vertex[2] = sphere_radius * cos(alpha) * sin(gamma);
|
---|
| 531 |
|
---|
| 532 | glNormal3dv(vertex);
|
---|
| 533 | glVertex3dv(vertex);
|
---|
| 534 |
|
---|
| 535 | }
|
---|
| 536 | glEnd();
|
---|
| 537 | }
|
---|
| 538 | glFrontFace(GL_CCW);
|
---|
| 539 | } |
---|