X-Git-Url: https://git.lukelau.me/?p=opengl.git;a=blobdiff_plain;f=main.cpp;h=742c8983840eff62fbb68652ba0365fe2da0c72b;hp=503f469bba97524bf92b10a64164a8d4bdbed39d;hb=85f8f7278f24fe73fef1a19174376b155319072f;hpb=5fa27af6222eab1f43e6ca01f1c37cbfa1d86fcd

diff --git a/main.cpp b/main.cpp
index 503f469..742c898 100644
--- a/main.cpp
+++ b/main.cpp
@@ -14,38 +14,77 @@
 #include <glm/glm.hpp>
 #include <glm/ext.hpp>
 #include <glm/gtc/type_ptr.hpp>
+#include "model.hpp"
+#include "teapot.h"
 
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
 
 using namespace std;
 
-GLuint* vaos;
-GLuint progId;
-glm::vec3 camPos   = glm::vec3(0.0f, 0.0f,  -5.0f);
+GLuint pyramidVao, lightVao, teapotVao;
+GLuint gradientProgId, plainProgId, normalProgId, solidProgId, textureProgId;
+glm::vec3 camPos   = glm::vec3(0.0f, 0.0f,  0.0f);
 glm::vec3 camFront = glm::vec3(0.0f, 0.0f, 1.0f);
 glm::vec3 camUp    = glm::vec3(0.0f, 1.0f,  0.0f);
 float yaw = 1.57, pitch = 0;
 bool doScale, doRotate, doTranslate;
+Model *monkeyHead, *chest;
+glm::vec3 lightPos(0);
 
-void display() {
-	glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
-	glUseProgram(progId);
-	glBindVertexArray(vaos[0]);
-	for (int i = 0; i < 100; i++) {
+const int WIDTH = 800, HEIGHT = 600;
+const float ASPECT = (float)WIDTH / (float)HEIGHT;
 
-		GLuint projId = glGetUniformLocation(progId, "projection");
-		glm::mat4 proj = glm::perspective(glm::radians(45.f), 1.33f, 0.01f, 10000.f);
-		glUniformMatrix4fv(projId, 1, GL_FALSE, glm::value_ptr(proj));
+void setProjectionAndViewUniforms(GLuint progId) {
+	GLuint projLoc = glGetUniformLocation(progId, "projection");
+	glm::mat4 proj = glm::perspective(glm::radians(45.f), ASPECT, 0.01f, 10000.f);
+	glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(proj));
 
-		GLuint viewId = glGetUniformLocation(progId, "view");
+	GLuint viewLoc = glGetUniformLocation(progId, "view");
 	glm::mat4 view = glm::lookAt(camPos, camPos + camFront, camUp);
-		glUniformMatrix4fv(viewId, 1, GL_FALSE, glm::value_ptr(view));
+	glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
+}
+
+void setLightColorAndPos(GLuint progId, glm::vec3 lightPos, glm::vec4 lightColor) {
+	GLuint lightColorLoc = glGetUniformLocation(progId, "lightColor");
+	glUniform4fv(lightColorLoc, 1, glm::value_ptr(lightColor));
+
+	GLuint lightPosLoc = glGetUniformLocation(progId, "vLightPos");
+	glUniform3fv(lightPosLoc, 1, glm::value_ptr(lightPos));
+
+	GLuint viewPosLoc = glGetUniformLocation(progId, "vViewPos");
+	glUniform3fv(viewPosLoc, 1, glm::value_ptr(camPos));
+}
+
+void drawLight(float d, glm::vec3 lightPos, glm::vec4 lightColor) {
+  	glUseProgram(plainProgId);
+	glBindVertexArray(lightVao);
+	setProjectionAndViewUniforms(plainProgId);
+	glm::mat4 model = glm::translate(glm::mat4(1.f), lightPos);
+	model = glm::scale(model, glm::vec3(0.2));
+	GLuint modelLoc = glGetUniformLocation(plainProgId, "model");
+	glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
+
+	GLuint colorLoc = glGetUniformLocation(plainProgId, "color");
+	glm::vec4 color(lightColor);
+	glUniform4fv(colorLoc, 1, glm::value_ptr(color));
+		
+	glDrawArrays(GL_TRIANGLES, 0, 36);
+};
+
+void drawPyramids(float d, glm::vec3 lightPos, glm::vec4 lightColor) {
+	glUseProgram(gradientProgId);
+	glBindVertexArray(pyramidVao);
+	setProjectionAndViewUniforms(gradientProgId);
+
+	setLightColorAndPos(gradientProgId, lightPos, lightColor);
+
+	GLuint modelId = glGetUniformLocation(gradientProgId, "model");
+
+	for (int i = 0; i < 10; i++) {
 
-		GLuint modelId = glGetUniformLocation(progId, "model");
-		float d = (float)glutGet(GLUT_ELAPSED_TIME) * 0.001f;
 		glm::mat4 model = glm::mat4(1.f);
 
-		model = glm::translate(model, glm::vec3(sin(i * 30) * 10, cos(i * 30) * 10, i * 2));
+		model = glm::translate(model, glm::vec3(sin(i * 30) * 10, 0, i * 2 - 10));
 		
 		if (doRotate) {
 			model = glm::rotate(model, d * glm::radians(30.f), glm::vec3(0.f, 1.f, 0.f));
@@ -61,8 +100,90 @@ void display() {
 
 		glUniformMatrix4fv(modelId, 1, GL_FALSE, glm::value_ptr(model));
 		
-		glDrawArrays(GL_TRIANGLES, 0, 12);
+		glDrawArrays(GL_TRIANGLES, 0, 18);
 	}
+
+};
+
+enum TeapotProjection { teapotOrtho, teapotCamera, teapotPerspStatic, teapotPerspAnimated };
+
+void drawTeapot(TeapotProjection proj, bool rotate, float d, glm::vec3 lightPos, glm::vec4 lightColor) {
+	glUseProgram(normalProgId);
+	
+	GLuint projLoc = glGetUniformLocation(normalProgId, "projection");
+	GLuint viewLoc = glGetUniformLocation(normalProgId, "view");
+	switch (proj) {
+	case teapotCamera:
+		setProjectionAndViewUniforms(normalProgId);
+		break;
+	case teapotOrtho:
+		{
+			glm::mat4 proj = glm::ortho(-5.f * ASPECT, 5.f * ASPECT, -5.f, 5.f, 0.01f, 1000.f);
+			glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(proj));
+
+			glm::vec3 camPos(-5, 5, -5), camFront = glm::vec3(0) - camPos;
+			glm::mat4 view = glm::lookAt(camPos, camPos + camFront, camUp);
+			glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
+		}
+		break;
+	case teapotPerspStatic:
+	case teapotPerspAnimated:
+		{
+			float fov = glm::radians(45.f);
+			if (proj == teapotPerspAnimated)
+				fov += glm::radians(sin(d) * 30.f);
+			glm::mat4 proj = glm::perspective(fov, ASPECT, 0.01f, 10000.f);
+			glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(proj));
+
+			glm::mat4 view = glm::lookAt(glm::vec3(0, 0, -10), glm::vec3(0), camUp);
+			glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
+		}
+		break;
+	}
+	setLightColorAndPos(normalProgId, lightPos, lightColor);
+	glBindVertexArray(teapotVao);
+	GLuint modelId = glGetUniformLocation(normalProgId, "model");
+	glm::mat4 model(1);
+	model = glm::scale(model, glm::vec3(0.3));
+	if (rotate) model = glm::rotate(model, d, glm::vec3(0, 1, 0));
+	glUniformMatrix4fv(modelId, 1, GL_FALSE, glm::value_ptr(model));
+
+	glDrawArrays(GL_TRIANGLES, 0, teapot_vertex_count);
+}
+
+void display() {
+	glClearColor(0.5, 0.5, 0.5, 1);
+	glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
+	float d = (float)glutGet(GLUT_ELAPSED_TIME) * 0.001f;
+
+	/* glm::vec3 lightPos = glm::vec3(sin(d / 10.f) * 10, 0, cos(d / 10.f) * 10); */
+	glm::vec4 lightColor(1, 1, 1, 1);
+
+	drawLight(d, lightPos, lightColor);
+
+	glUseProgram(textureProgId);
+	setProjectionAndViewUniforms(textureProgId);
+	setLightColorAndPos(textureProgId, lightPos, lightColor);
+
+	Model::Node *top = chest->find("top");
+	top->model = glm::translate(glm::mat4(1), glm::vec3(0, 1, -1));
+	top->model = glm::rotate(top->model, sin(d / 2.5f) * 0.5f, glm::vec3(1, 0, 0));
+	top->model = glm::translate(top->model, glm::vec3(0, -1, 1));
+	
+	/* Model::Node *jewels = chest->find("jewels"); */
+	/* jewels->model = glm::scale(glm::mat4(1), glm::vec3((sin(d) + 1.2f) / 2.f)); */
+
+	/* Model::Node *lock = chest->find("lock"); */
+	/* lock->model = glm::translate(glm::mat4(1), glm::vec3(0.22610, 3.36478, -0.75649)); */
+	/* lock->model = glm::rotate(lock->model, (d / 2.5f), glm::vec3(0, 1, 0.4)); */
+	/* lock->model = glm::translate(lock->model, -glm::vec3(0.22610, 3.36478, -0.75649)); */
+
+	/* Model::Node *key = chest->find("key"); */
+	/* key->model = glm::translate(glm::mat4(1), glm::vec3(0, 0, sin(d))); */
+	
+	/* chest->getRoot()->model = glm::translate(glm::mat4(1), lightPos); */
+	chest->draw();
+
 	glutSwapBuffers();
 }
 
@@ -114,7 +235,7 @@ GLuint compileShaders(char* vertexShader, char* fragmentShader) {
 
 #define BUFFER_OFFSET(i) ((char *)NULL + (i))
 
-GLuint setupBuffers(GLfloat* vertices, GLuint progId) {
+GLuint setupBuffers(glm::vec3* vertices, glm::vec3* normals, GLuint progId) {
 
 	GLfloat colors[] = {
 		0, 1, 0, 1,
@@ -129,12 +250,20 @@ GLuint setupBuffers(GLfloat* vertices, GLuint progId) {
 		1, 0, 0, 1,
 		0, 0, 1, 1,
 
+		0, 1, 0, 1,
+		1, 0, 0, 1,
+		0, 0, 1, 1,
+
+		0, 1, 0, 1,
+		1, 0, 0, 1,
+		0, 0, 1, 1,
+		
 		0, 1, 0, 1,
 		1, 0, 0, 1,
 		0, 0, 1, 1
 	};
 
-	GLuint numVerts = 12;
+	GLuint numVerts = 18;
 
 	GLuint vbo;
 	glGenBuffers(1, &vbo);
@@ -144,26 +273,141 @@ GLuint setupBuffers(GLfloat* vertices, GLuint progId) {
 
 	GLuint posId = glGetAttribLocation(progId, "vPosition");
 	GLuint colorId = glGetAttribLocation(progId, "vColor");
+	GLuint normalLoc = glGetAttribLocation(progId, "vNormal");
 
 	GLuint vertsLen = numVerts * 3 * sizeof(GLfloat);
 	GLuint colorsLen = numVerts * 4 * sizeof(GLfloat);
+	GLuint normalLen = numVerts * 3 * sizeof(GLfloat);
 
 	glBindBuffer(GL_ARRAY_BUFFER, vbo);
-	glBufferData(GL_ARRAY_BUFFER, vertsLen + colorsLen, NULL, GL_STATIC_DRAW);
+	glBufferData(GL_ARRAY_BUFFER, vertsLen + colorsLen + normalLen, NULL, GL_STATIC_DRAW);
 
-	glBufferSubData(GL_ARRAY_BUFFER, 0, vertsLen, vertices);
+	glBufferSubData(GL_ARRAY_BUFFER, 0, vertsLen, glm::value_ptr(vertices[0]));
 	glBufferSubData(GL_ARRAY_BUFFER, vertsLen, colorsLen, colors);
+	glBufferSubData(GL_ARRAY_BUFFER, vertsLen + colorsLen, normalLen, glm::value_ptr(normals[0]));
 	
 	glBindVertexArray(vao);
+
 	glEnableVertexAttribArray(posId);
 	glVertexAttribPointer(posId, 3, GL_FLOAT, GL_FALSE, 0, 0);
 
 	glEnableVertexAttribArray(colorId);
-	glVertexAttribPointer(colorId, 4, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(numVerts * 3 * sizeof(GLfloat)));
+	glVertexAttribPointer(colorId, 4, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(vertsLen));
+
+	glEnableVertexAttribArray(normalLoc);
+	glVertexAttribPointer(normalLoc, 3, GL_FLOAT, GL_FALSE, 0, BUFFER_OFFSET(vertsLen + colorsLen));
 
 	return vao;
 }
 
+vector<glm::vec3> quadToTriangles(glm::vec3 *quads) {
+	vector<glm::vec3> triangles(6);
+	triangles[0] = quads[0];
+	triangles[1] = quads[1];
+	triangles[2] = quads[2];
+	triangles[3] = quads[2];
+	triangles[4] = quads[3];
+	triangles[5] = quads[0];
+	return triangles;
+}
+
+template <typename T>
+void append(vector<T> &a, vector<T> &b) {
+	a.insert(a.end(), b.begin(), b.end());
+};
+
+void setupLightBuffers(GLuint progId) {
+  	vector<glm::vec3> vertices;
+	glm::vec3 front[] = {
+		glm::vec3(1, -1, -1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(-1, 1, -1),
+		glm::vec3(1, 1, -1)
+	};
+	vector<glm::vec3> frontTriangles = quadToTriangles(front);
+	append(vertices, frontTriangles);
+
+	glm::vec3 back[] = {
+		glm::vec3(1, 1, 1),
+		glm::vec3(-1, 1, 1),
+		glm::vec3(-1, -1, 1),
+		glm::vec3(1, -1, 1)
+	};
+	vector<glm::vec3> backQuads = quadToTriangles(back);
+	append(vertices, backQuads);
+
+	glm::vec3 top[] = {
+		glm::vec3(1, 1, -1),
+		glm::vec3(-1, 1, -1),
+		glm::vec3(-1, 1, 1),
+		glm::vec3(1, 1, 1)
+	};
+	vector<glm::vec3> topTriangles = quadToTriangles(top);
+	append(vertices, topTriangles);
+
+	glm::vec3 bottom[] = {
+		glm::vec3(1, -1, 1),
+		glm::vec3(-1, -1, 1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(1, -1, -1)
+	};
+	vector<glm::vec3> bottomTriangles = quadToTriangles(bottom);
+	append(vertices, bottomTriangles);
+
+	glm::vec3 left[] = {
+		glm::vec3(-1, 1, 1),
+		glm::vec3(-1, 1, -1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(-1, -1, 1)
+	};
+	vector<glm::vec3> leftTriangles = quadToTriangles(left);
+	append(vertices, leftTriangles);
+
+	glm::vec3 right[] = {
+		glm::vec3(1, 1, -1),
+		glm::vec3(1, 1, 1),
+		glm::vec3(1, -1, 1),
+		glm::vec3(1, -1, -1)
+	};
+	vector<glm::vec3> rightTriangles = quadToTriangles(right);
+	append(vertices, rightTriangles);
+	GLuint verticesSize = 36 * 3 * sizeof(GLfloat);
+
+	glGenVertexArrays(1, &lightVao);
+	GLuint vbo;
+	glBindVertexArray(lightVao);
+	glGenBuffers(1, &vbo);
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBufferData(GL_ARRAY_BUFFER, verticesSize, NULL, GL_STATIC_DRAW);
+	glBufferSubData(GL_ARRAY_BUFFER, 0, verticesSize, glm::value_ptr(vertices[0]));
+	GLuint posLoc = glGetAttribLocation(progId, "vPosition");
+	glEnableVertexAttribArray(posLoc);
+	glVertexAttribPointer(posLoc, 3, GL_FLOAT, GL_FALSE, 0, 0);
+}
+
+void setupTeapotBuffers(GLuint progId) {
+	GLuint vbos[2];
+	glGenBuffers(2, vbos);
+	glBindBuffer(GL_ARRAY_BUFFER, vbos[0]);
+	glBufferData(GL_ARRAY_BUFFER, 3 * teapot_vertex_count * sizeof(float), teapot_vertex_points, GL_STATIC_DRAW);
+	glBindBuffer(GL_ARRAY_BUFFER, vbos[1]);
+	glBufferData(GL_ARRAY_BUFFER, 3 * teapot_vertex_count * sizeof(float), teapot_normals, GL_STATIC_DRAW);
+
+	glGenVertexArrays(1, &teapotVao);
+	glBindVertexArray(teapotVao);
+
+	GLuint posLoc = glGetAttribLocation(progId, "vPosition");
+	GLuint normalLoc = glGetAttribLocation(progId, "vNormal");
+
+	glEnableVertexAttribArray(posLoc);
+	glBindBuffer(GL_ARRAY_BUFFER, vbos[0]);
+	glVertexAttribPointer(posLoc, 3, GL_FLOAT, GL_FALSE, 0, NULL);
+	
+	glEnableVertexAttribArray(normalLoc);
+	glBindBuffer(GL_ARRAY_BUFFER, vbos[1]);
+	glVertexAttribPointer(normalLoc, 3, GL_FLOAT, GL_FALSE, 0, NULL);
+}
+
 void validateProgram(GLuint progId) {
 	glValidateProgram(progId);
 	
@@ -178,33 +422,73 @@ void validateProgram(GLuint progId) {
 }
 
 void init() {
-	GLfloat vertices[9*4] = {
-		-1.0f, -1.0f, -1.0f,
-		1.0f, -1.0f, -1.0f,
-		0.0f, 1.0f, 0.0f,
+	glm::vec3 vertices[18] = {
+		glm::vec3(0.0f, 1.0f, 0.0f),
+		glm::vec3(1.0f, -1.0f, -1.0f),
+		glm::vec3(-1.0f, -1.0f, -1.0f),
+
+		glm::vec3(0.0f, 1.0f, 0.0f),
+		glm::vec3(-1.0f, -1.0f, 1.0f),
+		glm::vec3(1.0f, -1.0f, 1.0f),
+
+		glm::vec3(0.0f, 1.0f, 0.0f),
+		glm::vec3(-1.0f, -1.0f, -1.0f),
+		glm::vec3(-1.0f, -1.0f, 1.0f),
+
+		glm::vec3(0.0f, 1.0f, 0.0f),
+		glm::vec3(1.0f, -1.0f, 1.0f),
+		glm::vec3(1.0f, -1.0f, -1.0f),
+
+		glm::vec3(1, -1, 1),
+		glm::vec3(-1, -1, 1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(1, -1, -1),
+		glm::vec3(1, -1, 1)
+	};
+
+	// work out the normals
+	glm::vec3 normals[18];
+	for (int i = 0; i < 6; i++) {
+		glm::vec3 a = vertices[i * 3];
+		glm::vec3 b = vertices[i * 3 + 1];
+		glm::vec3 c = vertices[i * 3 + 2];
+		glm::vec3 u = glm::normalize(a - c);
+	  	glm::vec3 v = glm::normalize(b - c);
+		glm::vec3 norm = glm::normalize(glm::cross(v, u));
+		for(int j = 0; j < 3; j++) {
+			normals[i * 3 + j] = -glm::vec3(norm);
+		}
+	}
 
-		-1.0f, -1.0f, 1.0f,
-		1.0f, -1.0f, 1.0f,
-		0.0f, 1.0f, 0.0f,
+	gradientProgId = compileShaders((char*)"vertex.glsl", (char*)"gradientfrag.glsl");
+	glUseProgram(gradientProgId);
+	pyramidVao = setupBuffers(vertices, normals, gradientProgId);
+	validateProgram(gradientProgId);
 
-		-1.0f, -1.0f, -1.0f,
-		-1.0f, -1.0f, 1.0f,
-		0.0f, 1.0f, 0.0f,
+	plainProgId = compileShaders((char*)"plainvertex.glsl", (char*)"plainfrag.glsl");
+	glUseProgram(plainProgId);
+	setupLightBuffers(plainProgId);
+	validateProgram(plainProgId);
 
-		1.0f, -1.0f, -1.0f,
-		1.0f, -1.0f, 1.0f,
-		0.0f, 1.0f, 0.0f
+	normalProgId = compileShaders((char*)"vertex.glsl", (char*)"normalfrag.glsl");
+	glUseProgram(normalProgId);
+	setupTeapotBuffers(normalProgId);
+	validateProgram(normalProgId);
 
-	};
+	solidProgId = compileShaders((char*)"vertex.glsl", (char*)"solidfrag.glsl");
+	glUseProgram(solidProgId);
+	validateProgram(solidProgId);
 
-	vaos = new GLuint[2];
+	textureProgId = compileShaders((char*)"texturevertex.glsl", (char*)"texturefrag.glsl");
+	glUseProgram(textureProgId);
+	validateProgram(textureProgId);
 
-	progId = compileShaders((char*)"vertex.glsl", (char*)"fragment.glsl");
-	glUseProgram(progId);
-	vaos[0] = setupBuffers(vertices, progId);
-	validateProgram(progId);
+	monkeyHead = new Model("monkeyhead_smooth.dae", solidProgId);
+	chest = new Model("models/chest.dae", textureProgId);
 
 	glEnable(GL_DEPTH_TEST); 
+	glEnable(GL_CULL_FACE); 
 }
 
 bool* keyStates = new bool[256];
@@ -223,7 +507,7 @@ void keyboardUp(unsigned char key, int x, int y) {
 	keyStates[key] = false;
 }
 
-void idle(int _) {
+void timer(int _) {
 	float xSpeed = 0.f, ySpeed = 0.f, zSpeed = 0.f;
 	if (keyStates['w'])
 		zSpeed = 0.1f;
@@ -238,11 +522,18 @@ void idle(int _) {
 	if (keyStates['e'])
 		ySpeed = -0.1f;
 
+	if (keyStates['j']) lightPos.z += 0.1f;
+	if (keyStates['k']) lightPos.z -= 0.1f;
+	if (keyStates['h']) lightPos.x -= 0.1f;
+	if (keyStates['l']) lightPos.x += 0.1f;
+	if (keyStates['m']) lightPos.y -= 0.1f;
+	if (keyStates['n']) lightPos.y += 0.1f;
+
 	camPos.x += xSpeed * sin(yaw) + zSpeed * cos(yaw);
 	camPos.y += ySpeed;
 	camPos.z += zSpeed * sin(yaw) - xSpeed * cos(yaw);
 	glutPostRedisplay();
-	glutTimerFunc(16, idle, 0);
+	glutTimerFunc(16, timer, 0);
 }
 
 int prevMouseX, prevMouseY;
@@ -268,6 +559,12 @@ void motion(int x, int y) {
 	front.y = sin(pitch);
 	front.z = cos(pitch) * sin(yaw);
 	camFront = glm::normalize(front);
+
+	if (pitch < -1.57079632679 || pitch >= 1.57079632679) {
+		camUp = glm::vec3(0, -1, 0);
+	} else {
+		camUp = glm::vec3(0, 1, 0);
+	}
 }
 
 void mouse(int button, int state, int x, int y) {
@@ -278,7 +575,7 @@ void mouse(int button, int state, int x, int y) {
 int main(int argc, char** argv) {
 	glutInit(&argc, argv);
 	glutInitDisplayMode(GLUT_DEPTH|GLUT_DOUBLE|GLUT_RGB|GLUT_3_2_CORE_PROFILE);
-	glutInitWindowSize(800, 600);
+	glutInitWindowSize(WIDTH, HEIGHT);
 	int win = glutCreateWindow("Hello Triangle");
 	glutDisplayFunc(display);
 
@@ -288,7 +585,7 @@ int main(int argc, char** argv) {
 
 	glutKeyboardFunc(keyboard);
 	glutKeyboardUpFunc(keyboardUp);
-	glutTimerFunc(16, idle, 0);
+	glutTimerFunc(16, timer, 0);
 	glutMotionFunc(motion);
 	glutMouseFunc(mouse);