11 #include <OpenGL/glew.h>
13 #include <GLUT/glut.h>
14 #include <glm/glm.hpp>
15 #include <glm/ext.hpp>
16 #include <glm/gtc/type_ptr.hpp>
18 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
22 GLuint pyramidVao, lightVao;
23 GLuint gradientProgId, solidProgId;
24 glm::vec3 camPos = glm::vec3(0.0f, 0.0f, -5.0f);
25 glm::vec3 camFront = glm::vec3(0.0f, 0.0f, 1.0f);
26 glm::vec3 camUp = glm::vec3(0.0f, 1.0f, 0.0f);
27 float yaw = 1.57, pitch = 0;
28 bool doScale, doRotate, doTranslate;
30 void setProjectionAndViewUniforms(GLuint progId) {
31 GLuint projId = glGetUniformLocation(progId, "projection");
32 glm::mat4 proj = glm::perspective(glm::radians(45.f), 1.33f, 0.01f, 10000.f);
33 glUniformMatrix4fv(projId, 1, GL_FALSE, glm::value_ptr(proj));
35 GLuint viewId = glGetUniformLocation(progId, "view");
36 glm::mat4 view = glm::lookAt(camPos, camPos + camFront, camUp);
37 glUniformMatrix4fv(viewId, 1, GL_FALSE, glm::value_ptr(view));
40 void drawLight(float d, glm::vec3 lightPos) {
41 glUseProgram(solidProgId);
42 glBindVertexArray(lightVao);
43 setProjectionAndViewUniforms(solidProgId);
44 glm::mat4 model = glm::translate(glm::mat4(1.f), lightPos);
45 model = glm::scale(model, glm::vec3(0.2));
46 GLuint modelId = glGetUniformLocation(solidProgId, "model");
47 glUniformMatrix4fv(modelId, 1, GL_FALSE, glm::value_ptr(model));
49 GLuint colorLoc = glGetUniformLocation(solidProgId, "color");
50 glm::vec3 color = glm::vec3(1, 1, 1);
51 glUniform3fv(colorLoc, 1, glm::value_ptr(color));
53 glDrawArrays(GL_TRIANGLES, 0, 36);
56 void drawPyramids(float d, glm::vec3 lightPos) {
57 glUseProgram(gradientProgId);
58 glBindVertexArray(pyramidVao);
59 setProjectionAndViewUniforms(gradientProgId);
61 GLuint lightPosLoc = glGetUniformLocation(gradientProgId, "lightPos");
62 glUniform3fv(lightPosLoc, 1, glm::value_ptr(lightPos));
64 GLuint viewPosLoc = glGetUniformLocation(gradientProgId, "viewPos");
65 glUniform3fv(viewPosLoc, 1, glm::value_ptr(camPos));
67 GLuint modelId = glGetUniformLocation(gradientProgId, "model");
69 for (int i = 0; i < 10; i++) {
71 glm::mat4 model = glm::mat4(1.f);
73 model = glm::translate(model, glm::vec3(sin(i * 30) * 10, 0, i * 2 - 10));
76 model = glm::rotate(model, d * glm::radians(30.f), glm::vec3(0.f, 1.f, 0.f));
77 model = glm::rotate(model, d * glm::radians(20.f), glm::vec3(1.f, 0.f, 0.f));
81 model = glm::scale(model, glm::vec3(1.f, 0.7f + 0.7f * (1 + sin(d + (i + 3))), 1.f));
84 model = glm::translate(model, glm::vec3(sin(d + (i + 1)), cos(d + (i + -3)), sin(d + (i + 4))));
87 glUniformMatrix4fv(modelId, 1, GL_FALSE, glm::value_ptr(model));
89 glDrawArrays(GL_TRIANGLES, 0, 18);
95 glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
96 float d = (float)glutGet(GLUT_ELAPSED_TIME) * 0.001f;
98 glm::vec3 lightPos = glm::vec3(sin(d) * 10, 0, cos(d) * 10);
100 drawPyramids(d, lightPos);
101 drawLight(d, lightPos);
106 void attachShader(GLuint progId, const char* filePath, GLenum type) {
107 GLuint shader = glCreateShader(type);
110 fprintf(stderr, "error creating shader\n");
114 ifstream file(filePath);
116 buffer << file.rdbuf();
117 string str = buffer.str();
118 const char* contents = str.c_str();
120 glShaderSource(shader, 1, (const GLchar**)&contents, NULL);
121 glCompileShader(shader);
123 glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
126 glGetShaderInfoLog(shader, 1024, NULL, log);
127 fprintf(stderr, "error: %s\n", log);
130 glAttachShader(progId, shader);
133 GLuint compileShaders(char* vertexShader, char* fragmentShader) {
134 GLuint progId = glCreateProgram();
136 attachShader(progId, vertexShader, GL_VERTEX_SHADER);
137 attachShader(progId, fragmentShader, GL_FRAGMENT_SHADER);
139 glLinkProgram(progId);
141 glGetProgramiv(progId, GL_LINK_STATUS, &success);
144 glGetProgramInfoLog(progId, sizeof(log), NULL, log);
145 fprintf(stderr, "error linking: %s\n", log);
152 #define BUFFER_OFFSET(i) ((char *)NULL + (i))
154 GLuint setupBuffers(glm::vec3* vertices, glm::vec3* normals, GLuint progId) {
182 GLuint numVerts = 18;
185 glGenBuffers(1, &vbo);
188 glGenVertexArrays(1, &vao);
190 GLuint posId = glGetAttribLocation(progId, "vPosition");
191 GLuint colorId = glGetAttribLocation(progId, "vColor");
192 GLuint normalLoc = glGetAttribLocation(progId, "vNormal");
194 GLuint vertsLen = numVerts * 3 * sizeof(GLfloat);
195 GLuint colorsLen = numVerts * 4 * sizeof(GLfloat);
196 GLuint normalLen = numVerts * 3 * sizeof(GLfloat);
198 glBindBuffer(GL_ARRAY_BUFFER, vbo);
199 glBufferData(GL_ARRAY_BUFFER, vertsLen + colorsLen + normalLen, NULL, GL_STATIC_DRAW);
201 glBufferSubData(GL_ARRAY_BUFFER, 0, vertsLen, glm::value_ptr(vertices[0]));
202 glBufferSubData(GL_ARRAY_BUFFER, vertsLen, colorsLen, colors);
203 glBufferSubData(GL_ARRAY_BUFFER, vertsLen + colorsLen, normalLen, glm::value_ptr(normals[0]));
205 glBindVertexArray(vao);
207 glEnableVertexAttribArray(posId);
208 glVertexAttribPointer(posId, 3, GL_FLOAT, GL_FALSE, 0, 0);
210 glEnableVertexAttribArray(colorId);
211 glVertexAttribPointer(colorId, 4, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(vertsLen));
213 glEnableVertexAttribArray(normalLoc);
214 glVertexAttribPointer(normalLoc, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(vertsLen + colorsLen));
219 vector<glm::vec3> quadToTriangles(glm::vec3 *quads) {
220 vector<glm::vec3> triangles(6);
221 triangles[0] = quads[0];
222 triangles[1] = quads[1];
223 triangles[2] = quads[2];
224 triangles[3] = quads[2];
225 triangles[4] = quads[3];
226 triangles[5] = quads[0];
230 template <typename T>
231 void append(vector<T> &a, vector<T> &b) {
232 a.insert(a.end(), b.begin(), b.end());
235 void setupLightBuffers(GLuint progId) {
236 vector<glm::vec3> vertices;
237 glm::vec3 front[] = {
238 glm::vec3(1, -1, -1),
239 glm::vec3(-1, -1, -1),
240 glm::vec3(-1, 1, -1),
243 vector<glm::vec3> frontTriangles = quadToTriangles(front);
244 append(vertices, frontTriangles);
249 glm::vec3(-1, -1, 1),
252 vector<glm::vec3> backQuads = quadToTriangles(back);
253 append(vertices, backQuads);
257 glm::vec3(-1, 1, -1),
261 vector<glm::vec3> topTriangles = quadToTriangles(top);
262 append(vertices, topTriangles);
264 glm::vec3 bottom[] = {
266 glm::vec3(-1, -1, 1),
267 glm::vec3(-1, -1, -1),
270 vector<glm::vec3> bottomTriangles = quadToTriangles(bottom);
271 append(vertices, bottomTriangles);
275 glm::vec3(-1, 1, -1),
276 glm::vec3(-1, -1, -1),
279 vector<glm::vec3> leftTriangles = quadToTriangles(left);
280 append(vertices, leftTriangles);
282 glm::vec3 right[] = {
288 vector<glm::vec3> rightTriangles = quadToTriangles(right);
289 append(vertices, rightTriangles);
290 GLuint verticesSize = 36 * 3 * sizeof(GLfloat);
292 glGenVertexArrays(1, &lightVao);
294 glBindVertexArray(lightVao);
295 glGenBuffers(1, &vbo);
296 glBindBuffer(GL_ARRAY_BUFFER, vbo);
297 glBufferData(GL_ARRAY_BUFFER, verticesSize, NULL, GL_STATIC_DRAW);
298 glBufferSubData(GL_ARRAY_BUFFER, 0, verticesSize, glm::value_ptr(vertices[0]));
299 GLuint posLoc = glGetAttribLocation(progId, "vPosition");
300 glEnableVertexAttribArray(posLoc);
301 glVertexAttribPointer(posLoc, 3, GL_FLOAT, GL_FALSE, 0, 0);
304 void validateProgram(GLuint progId) {
305 glValidateProgram(progId);
308 glGetProgramiv(progId, GL_VALIDATE_STATUS, &success);
311 glGetProgramInfoLog(progId, sizeof(log), NULL, log);
312 fprintf(stderr, "error: %s\n", log);
318 glm::vec3 vertices[18] = {
319 glm::vec3(0.0f, 1.0f, 0.0f),
320 glm::vec3(1.0f, -1.0f, -1.0f),
321 glm::vec3(-1.0f, -1.0f, -1.0f),
323 glm::vec3(0.0f, 1.0f, 0.0f),
324 glm::vec3(-1.0f, -1.0f, 1.0f),
325 glm::vec3(1.0f, -1.0f, 1.0f),
327 glm::vec3(0.0f, 1.0f, 0.0f),
328 glm::vec3(-1.0f, -1.0f, -1.0f),
329 glm::vec3(-1.0f, -1.0f, 1.0f),
331 glm::vec3(0.0f, 1.0f, 0.0f),
332 glm::vec3(1.0f, -1.0f, 1.0f),
333 glm::vec3(1.0f, -1.0f, -1.0f),
336 glm::vec3(-1, -1, 1),
337 glm::vec3(-1, -1, -1),
338 glm::vec3(-1, -1, -1),
339 glm::vec3(1, -1, -1),
343 // work out the normals
344 glm::vec3 normals[18];
345 for (int i = 0; i < 6; i++) {
346 glm::vec3 a = vertices[i * 3];
347 glm::vec3 b = vertices[i * 3 + 1];
348 glm::vec3 c = vertices[i * 3 + 2];
349 glm::vec3 u = glm::normalize(a - c);
350 glm::vec3 v = glm::normalize(b - c);
351 glm::vec3 norm = glm::normalize(glm::cross(v, u));
352 for(int j = 0; j < 3; j++) {
353 normals[i * 3 + j] = glm::vec3(norm);
357 gradientProgId = compileShaders((char*)"vertex.glsl", (char*)"fragment.glsl");
358 glUseProgram(gradientProgId);
359 pyramidVao = setupBuffers(vertices, normals, gradientProgId);
360 validateProgram(gradientProgId);
362 solidProgId = compileShaders((char*)"solidvertex.glsl", (char*)"solidfrag.glsl");
363 glUseProgram(solidProgId);
364 setupLightBuffers(solidProgId);
365 validateProgram(solidProgId);
367 glEnable(GL_DEPTH_TEST);
368 glEnable(GL_CULL_FACE);
371 bool* keyStates = new bool[256];
373 void keyboard(unsigned char key, int x, int y) {
374 keyStates[key] = true;
378 doRotate = !doRotate;
380 doTranslate = !doTranslate;
383 void keyboardUp(unsigned char key, int x, int y) {
384 keyStates[key] = false;
388 float xSpeed = 0.f, ySpeed = 0.f, zSpeed = 0.f;
402 camPos.x += xSpeed * sin(yaw) + zSpeed * cos(yaw);
404 camPos.z += zSpeed * sin(yaw) - xSpeed * cos(yaw);
406 glutTimerFunc(16, timer, 0);
409 int prevMouseX, prevMouseY;
410 bool firstMouse = true;
412 void motion(int x, int y) {
418 int dx = x - prevMouseX, dy = y - prevMouseY;
423 const float sensitivity = 0.005f;
424 yaw += dx * sensitivity;
425 pitch -= dy * sensitivity;
428 front.x = cos(pitch) * cos(yaw);
429 front.y = sin(pitch);
430 front.z = cos(pitch) * sin(yaw);
431 camFront = glm::normalize(front);
434 void mouse(int button, int state, int x, int y) {
435 if (button == GLUT_LEFT_BUTTON && state == GLUT_UP)
439 int main(int argc, char** argv) {
440 glutInit(&argc, argv);
441 glutInitDisplayMode(GLUT_DEPTH|GLUT_DOUBLE|GLUT_RGB|GLUT_3_2_CORE_PROFILE);
442 glutInitWindowSize(800, 600);
443 int win = glutCreateWindow("Hello Triangle");
444 glutDisplayFunc(display);
450 glutKeyboardFunc(keyboard);
451 glutKeyboardUpFunc(keyboardUp);
452 glutTimerFunc(16, timer, 0);
453 glutMotionFunc(motion);
454 glutMouseFunc(mouse);