render.c

   1 #include <GL/glut.h>
   2 #include <stdbool.h>
   3
   4 #include "assimp_types.h"
   5
   6 #include "level.h"
   7 #include "performance.h"
   8 #include "typedefs.h"
   9
  10 const float AXIS_RADIUS = 5.0f;
  11
  12 static void drawAxes();
  13 static void renderBlockGrid(const BlockGrid grid);
  14 static void drawBlock(const Block* block);
  15
  16 void initRender() {
  17         glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
  18
  19         GLfloat light0_ambient[] = {0.1f, 0.1f, 0.1f, 1.0f};
  20         GLfloat light0_diffuse[] = {1.0f, 1.0f, 1.0f, 1.0f};
  21         GLfloat light0_specular[] = {1.0f, 1.0f, 1.0f, 1.0f};
  22         GLfloat light0_position[] = {5.0f, 10.0f, 5.0f, 1.0f};
  23
  24         glLightfv(GL_LIGHT0, GL_AMBIENT, light0_ambient);
  25         glLightfv(GL_LIGHT0, GL_DIFFUSE, light0_diffuse);
  26         glLightfv(GL_LIGHT0, GL_SPECULAR, light0_specular);
  27         glLightfv(GL_LIGHT0, GL_POSITION, light0_position);
  28
  29         glLightf(GL_LIGHT0, GL_CONSTANT_ATTENUATION, 1.0f);
  30         glLightf(GL_LIGHT0, GL_LINEAR_ATTENUATION, 0.05f);
  31         glLightf(GL_LIGHT0, GL_QUADRATIC_ATTENUATION, 0.005f);
  32 }
  33
  34 void renderScene() {
  35         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
  36         glLoadIdentity();
  37
  38         glEnable(GL_NORMALIZE);
  39         glEnable(GL_CULL_FACE);
  40         glEnable(GL_DEPTH_TEST);
  41
  42         glDisable(GL_LIGHTING);
  43         drawAxes();
  44         glEnable(GL_LIGHTING);
  45
  46         glEnable(GL_LIGHT0);
  47         glEnable(GL_TEXTURE_2D);
  48         renderBlockGrid(levelGrid);
  49         glDisable(GL_TEXTURE_2D);
  50         glDisable(GL_LIGHT0);
  51
  52         glFlush();
  53         glutSwapBuffers();
  54         frameRendered();
  55         glutPostRedisplay();
  56 }
  57
  58 static void drawAxes() {
  59         point3f xAxisStart = { 0.0f, 0.0f, 0.0f };
  60         point3f xAxisEnd = { AXIS_RADIUS, 0.0f, 0.0f };
  61         point3f yAxisStart = { 0.0f, 0.0f, 0.0f };
  62         point3f yAxisEnd = { 0.0f, AXIS_RADIUS, 0.0f };
  63         point3f zAxisStart = { 0.0f, 0.0f, 0.0f };
  64         point3f zAxisEnd = { 0.0f, 0.0f, AXIS_RADIUS };
  65
  66         glColor3f(1.0f, 0.0f, 0.0f);
  67         glBegin(GL_LINES);
  68         glVertex3fv(xAxisStart);
  69         glVertex3fv(xAxisEnd);
  70         glEnd();
  71
  72         glColor3f(0.0f, 1.0f, 0.0f);
  73         glBegin(GL_LINES);
  74         glVertex3fv(yAxisStart);
  75         glVertex3fv(yAxisEnd);
  76         glEnd();
  77
  78         glColor3f(0.0f, 0.0f, 1.0f);
  79         glBegin(GL_LINES);
  80         glVertex3fv(zAxisStart);
  81         glVertex3fv(zAxisEnd);
  82         glEnd();
  83 }
  84
  85 static void renderBlockGrid(const BlockGrid grid) {
  86         glMatrixMode(GL_MODELVIEW);
  87         for (int z = 0; z < grid.depth; ++z) {
  88                 glLoadIdentity();
  89                 glTranslatef(0.0f, 0.0f, z * BLOCKGRID_CELL_SIZE);
  90                 for (int x = 0; x < grid.width; ++x) {
  91                         drawBlock(getBlockFromGrid(grid, x, z));
  92                         glTranslatef(BLOCKGRID_CELL_SIZE, 0.0f, 0.0f);
  93                 }
  94         }
  95         glLoadIdentity();
  96 }
  97
  98 static void drawBlock(const Block* block) {
  99         if (block->sceneData == NULL) {
 100                 return;
 101         }
 102
 103         glColor3f(0.5f, 1.0f, 0.0f);
 104
 105         for (int i = 0; i < block->sceneData->mNumMeshes; ++i) {
 106                 glBindTexture(GL_TEXTURE_2D, block->textureIds[i]);
 107                 const AiMesh* mesh = block->sceneData->mMeshes[i];
 108                 bool hasNormals = mesh->mNormals != NULL;
 109                 bool hasTextureCoords = mesh->mTextureCoords[0] != NULL;
 110
 111                 for (int k = 0; k < mesh->mNumFaces; ++k) {
 112                         const AiFace face = mesh->mFaces[k];
 113
 114                         GLenum faceMode;
 115                         switch (face.mNumIndices) {
 116                                 case 1: faceMode = GL_POINTS; break;
 117                                 case 2: faceMode = GL_LINES; break;
 118                                 case 3: faceMode = GL_TRIANGLES; break;
 119                                 default: faceMode = GL_POLYGON; break;
 120                         }
 121
 122                         glBegin(faceMode);
 123
 124                         for (int l = 0; l < face.mNumIndices; ++l) {
 125                                 unsigned int vertexIndex = face.mIndices[l];
 126                                 if (hasNormals) {
 127                                         if (hasTextureCoords) {
 128                                                 AiVector3D coords = mesh->mTextureCoords[0][vertexIndex];
 129                                                 glTexCoord2f(coords.x, coords.y);
 130                                         }
 131                                         glNormal3fv(&mesh->mNormals[vertexIndex].x);
 132                                 }
 133                                 glVertex3fv((const GLfloat*) &mesh->mVertices[vertexIndex]);
 134                         }
 135
 136                         glEnd();
 137                 }
 138         }
 139         glBindTexture(GL_TEXTURE_2D, 0);
 140 }