From: Luke Lau <luke_lau@icloud.com>
Date: Tue, 6 Nov 2018 22:48:27 +0000 (+0000)
Subject: Skybox
X-Git-Tag: cs7gv3-a3~23
X-Git-Url: http://git.lukelau.me/?p=opengl.git;a=commitdiff_plain;h=c44e69ec78367fb2957324026894aef970f2481a

Skybox
---

diff --git a/Makefile b/Makefile
index acf1a24..30f1503 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 all: main
 
 main:
-	clang++ -g --std=c++11 *.cpp -L/usr/local/lib -lassimp -framework OpenGL -framework glut -framework CoreGraphics -framework CoreFoundation -lglew -o bin/main
+	clang++ -g --std=c++17 *.cpp -L/usr/local/lib -lassimp -framework OpenGL -framework glut -framework CoreGraphics -framework CoreFoundation -lglew -o bin/main
 	ctags *.cpp
diff --git a/image.cpp b/image.cpp
new file mode 100644
index 0000000..71114b0
--- /dev/null
+++ b/image.cpp
@@ -0,0 +1,31 @@
+#include "image.hpp"
+
+Image::Image(const std::string &path) {
+	auto provider = CGDataProviderCreateWithFilename(path.c_str());
+	std::ifstream file(path);
+	long magic;
+	file.read((char*)&magic, 8);
+	file.close();
+
+	CGImageRef ref;
+
+	if (magic == 0x0a1a0a0d474e5089) // png magic number
+		ref = CGImageCreateWithPNGDataProvider(provider, nullptr, false, kCGRenderingIntentDefault);
+	else
+		ref = CGImageCreateWithJPEGDataProvider(provider, nullptr, false, kCGRenderingIntentDefault);
+
+	_width = CGImageGetWidth(ref), _height = CGImageGetHeight(ref);
+
+	dataRef = CGDataProviderCopyData(CGImageGetDataProvider(ref));
+	CGImageRelease(ref);
+
+}
+
+unsigned char *Image::data() {
+	return (unsigned char*) CFDataGetBytePtr(dataRef);
+}
+
+GLfloat Image::width() const { return _width; }
+GLfloat Image::height() const { return _height; }
+
+Image::~Image() { CFRelease(dataRef); }
diff --git a/image.hpp b/image.hpp
new file mode 100644
index 0000000..b6d7920
--- /dev/null
+++ b/image.hpp
@@ -0,0 +1,20 @@
+#include <iostream>
+#include <fstream>
+#ifdef __APPLE__
+#include <CoreGraphics/CoreGraphics.h>
+#include <GL/glew.h>
+#endif
+
+class Image {
+	public:
+		Image(const std::string &path);
+		~Image();
+		unsigned char *data();
+		GLfloat width() const;
+	   	GLfloat height() const;
+	private:
+		#ifdef __APPLE__
+		CFDataRef dataRef;
+		GLfloat _width, _height;
+		#endif
+};
diff --git a/main.cpp b/main.cpp
index 742c898..613d679 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1,8 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <iostream>
-#include <fstream>
-#include <sstream>
 #include <array>
 #include <vector>
 #ifdef __APPLE__
@@ -11,36 +9,49 @@
 #include <OpenGL/glew.h>
 #endif
 #include <GLUT/glut.h>
+#include "shapes.hpp"
 #include <glm/glm.hpp>
 #include <glm/ext.hpp>
 #include <glm/gtc/type_ptr.hpp>
 #include "model.hpp"
-#include "teapot.h"
+#include "program.hpp"
+#include "skybox.hpp"
 
 #pragma clang diagnostic ignored "-Wdeprecated-declarations"
 
 using namespace std;
 
-GLuint pyramidVao, lightVao, teapotVao;
-GLuint gradientProgId, plainProgId, normalProgId, solidProgId, textureProgId;
+GLuint lightVao;
+
+Program *textureProg, *plainProg;
+Skybox *skybox;
+	  		  
 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;
+Model *chest;
 glm::vec3 lightPos(0);
 
 const int WIDTH = 800, HEIGHT = 600;
 const float ASPECT = (float)WIDTH / (float)HEIGHT;
 
+glm::mat4 projMat() {
+	return glm::perspective(glm::radians(45.f), ASPECT, 0.01f, 10000.f);
+}
+
+glm::mat4 viewMat() {
+	return glm::lookAt(camPos, camPos + camFront, camUp);
+}
+
 void setProjectionAndViewUniforms(GLuint progId) {
 	GLuint projLoc = glGetUniformLocation(progId, "projection");
-	glm::mat4 proj = glm::perspective(glm::radians(45.f), ASPECT, 0.01f, 10000.f);
+	glm::mat4 proj = projMat();
 	glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(proj));
 
 	GLuint viewLoc = glGetUniformLocation(progId, "view");
-	glm::mat4 view = glm::lookAt(camPos, camPos + camFront, camUp);
+	glm::mat4 view = viewMat();
 	glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
 }
 
@@ -56,114 +67,36 @@ void setLightColorAndPos(GLuint progId, glm::vec3 lightPos, glm::vec4 lightColor
 }
 
 void drawLight(float d, glm::vec3 lightPos, glm::vec4 lightColor) {
-  	glUseProgram(plainProgId);
+  	glUseProgram(plainProg->progId);
 	glBindVertexArray(lightVao);
-	setProjectionAndViewUniforms(plainProgId);
+	setProjectionAndViewUniforms(plainProg->progId);
 	glm::mat4 model = glm::translate(glm::mat4(1.f), lightPos);
 	model = glm::scale(model, glm::vec3(0.2));
-	GLuint modelLoc = glGetUniformLocation(plainProgId, "model");
+	GLuint modelLoc = glGetUniformLocation(plainProg->progId, "model");
 	glUniformMatrix4fv(modelLoc, 1, GL_FALSE, glm::value_ptr(model));
 
-	GLuint colorLoc = glGetUniformLocation(plainProgId, "color");
+	GLuint colorLoc = glGetUniformLocation(plainProg->progId, "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++) {
-
-		glm::mat4 model = glm::mat4(1.f);
-
-		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));
-			model = glm::rotate(model, d * glm::radians(20.f), glm::vec3(1.f, 0.f, 0.f));
 }
 
-		if (doScale)
-			model = glm::scale(model, glm::vec3(1.f, 0.7f + 0.7f * (1 + sin(d + (i + 3))), 1.f));
-
-		if (doTranslate)
-			model = glm::translate(model, glm::vec3(sin(d + (i + 1)), cos(d + (i + -3)), sin(d + (i + 4))));
-	
-
-		glUniformMatrix4fv(modelId, 1, GL_FALSE, glm::value_ptr(model));
-		
-		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); */
+	skybox->draw(projMat(), viewMat());
+
 	glm::vec4 lightColor(1, 1, 1, 1);
 
 	drawLight(d, lightPos, lightColor);
 
-	glUseProgram(textureProgId);
-	setProjectionAndViewUniforms(textureProgId);
-	setLightColorAndPos(textureProgId, lightPos, lightColor);
+	glUseProgram(textureProg->progId);
+	setProjectionAndViewUniforms(textureProg->progId);
+	setLightColorAndPos(textureProg->progId, lightPos, lightColor);
 
 	Model::Node *top = chest->find("top");
 	top->model = glm::translate(glm::mat4(1), glm::vec3(0, 1, -1));
@@ -187,190 +120,8 @@ void display() {
 	glutSwapBuffers();
 }
 
-void attachShader(GLuint progId, const char* filePath, GLenum type) {
-	GLuint shader = glCreateShader(type);
-
-	if (!shader) {
-		fprintf(stderr, "error creating shader\n");
-		exit(1);
-	}
-
-	ifstream file(filePath);
-	stringstream buffer;
-	buffer << file.rdbuf();
-	string str = buffer.str();
-	const char* contents = str.c_str();
-
-	glShaderSource(shader, 1, (const GLchar**)&contents, NULL);
-	glCompileShader(shader);
-	GLint success;
-	glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
-	if (!success) {
-		GLchar log[1024];
-		glGetShaderInfoLog(shader, 1024, NULL, log);
-		fprintf(stderr, "error: %s\n", log);
-		exit(1);
-	}
-	glAttachShader(progId, shader);
-}
-
-GLuint compileShaders(char* vertexShader, char* fragmentShader) {
-	GLuint progId = glCreateProgram();
-
-	attachShader(progId, vertexShader, GL_VERTEX_SHADER);
-	attachShader(progId, fragmentShader, GL_FRAGMENT_SHADER);
-
-	glLinkProgram(progId);
-	GLint success = 0;
-	glGetProgramiv(progId, GL_LINK_STATUS, &success);
-	if (!success) {
-		GLchar log[1024];
-		glGetProgramInfoLog(progId, sizeof(log), NULL, log);
-		fprintf(stderr, "error linking: %s\n", log);
-		exit(1);
-	}
-
-	return progId;
-}
-
-#define BUFFER_OFFSET(i) ((char *)NULL + (i))
-
-GLuint setupBuffers(glm::vec3* vertices, glm::vec3* normals, GLuint progId) {
-
-	GLfloat colors[] = {
-		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,
-
-		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 = 18;
-
-	GLuint vbo;
-	glGenBuffers(1, &vbo);
-
-	GLuint vao;
-	glGenVertexArrays(1, &vao);
-
-	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 + normalLen, NULL, GL_STATIC_DRAW);
-
-	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(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);
+  	auto vertices = cube();
 	GLuint verticesSize = 36 * 3 * sizeof(GLfloat);
 
 	glGenVertexArrays(1, &lightVao);
@@ -385,29 +136,6 @@ void setupLightBuffers(GLuint progId) {
 	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);
 	
@@ -422,70 +150,25 @@ void validateProgram(GLuint progId) {
 }
 
 void init() {
-	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)
+	plainProg = new Program("plainvertex.glsl", "plainfrag.glsl");
+	glUseProgram(plainProg->progId);
+	setupLightBuffers(plainProg->progId);
+	validateProgram(plainProg->progId);
+
+	textureProg = new Program("texturevertex.glsl", "texturefrag.glsl");
+	glUseProgram(textureProg->progId);
+
+	chest = new Model("models/chest.dae", *textureProg);
+
+	std::vector<std::string> faces = {
+		"models/skybox/right.jpg",
+		"models/skybox/left.jpg",
+		"models/skybox/top.jpg",
+		"models/skybox/bottom.jpg",
+		"models/skybox/front.jpg",
+		"models/skybox/back.jpg"
 	};
-
-	// 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);
-		}
-	}
-
-	gradientProgId = compileShaders((char*)"vertex.glsl", (char*)"gradientfrag.glsl");
-	glUseProgram(gradientProgId);
-	pyramidVao = setupBuffers(vertices, normals, gradientProgId);
-	validateProgram(gradientProgId);
-
-	plainProgId = compileShaders((char*)"plainvertex.glsl", (char*)"plainfrag.glsl");
-	glUseProgram(plainProgId);
-	setupLightBuffers(plainProgId);
-	validateProgram(plainProgId);
-
-	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);
-
-	textureProgId = compileShaders((char*)"texturevertex.glsl", (char*)"texturefrag.glsl");
-	glUseProgram(textureProgId);
-	validateProgram(textureProgId);
-
-	monkeyHead = new Model("monkeyhead_smooth.dae", solidProgId);
-	chest = new Model("models/chest.dae", textureProgId);
+	skybox = new Skybox(faces);
 
 	glEnable(GL_DEPTH_TEST); 
 	glEnable(GL_CULL_FACE); 
diff --git a/material.cpp b/material.cpp
index 7cd8d80..0e655a1 100644
--- a/material.cpp
+++ b/material.cpp
@@ -1,7 +1,5 @@
 #include "material.hpp"
-#include <iostream>
-#include <fstream>
-#include <CoreGraphics/CoreGraphics.h>
+#include "image.hpp"
 
 Material::Material(const aiMaterial &ai, GLuint progId): progId(progId) {
 	if (ai.GetTextureCount(aiTextureType_DIFFUSE) > 0) {
@@ -26,31 +24,11 @@ Material::Material(const aiMaterial &ai, GLuint progId): progId(progId) {
 }
 
 Material::Texture::Texture(const std::string &fileName) {
-	auto path = "models/" + fileName;
-	auto provider = CGDataProviderCreateWithFilename(path.c_str());
-	std::ifstream file(path);
-	long magic;
-	file.read((char*)&magic, 8);
-	file.close();
-
-	CGImageRef ref;
-
-	if (magic == 0x0a1a0a0d474e5089) // png magic number
-		ref = CGImageCreateWithPNGDataProvider(provider, nullptr, false, kCGRenderingIntentDefault);
-	else
-		ref = CGImageCreateWithJPEGDataProvider(provider, nullptr, false, kCGRenderingIntentDefault);
-	
-	auto dataRef = CGDataProviderCopyData(CGImageGetDataProvider(ref));
-	auto img = (unsigned char*) CFDataGetBytePtr(dataRef);
-
 	glGenTextures(1, &texId);
 	glBindTexture(GL_TEXTURE_2D, texId);
-	auto width = CGImageGetWidth(ref), height = CGImageGetHeight(ref);
-	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, img);
+	Image img("models/" + fileName);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, img.width(), img.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img.data());
 	glGenerateMipmap(GL_TEXTURE_2D);
-
-	CGImageRelease(ref);
-	CFRelease(dataRef);
 }
 
 void Material::bind() const {
diff --git a/model.cpp b/model.cpp
index 8046e29..524b913 100644
--- a/model.cpp
+++ b/model.cpp
@@ -132,7 +132,7 @@ void Model::Node::draw(	const std::vector<Mesh> &meshes,
 	for (Node *child: children) child->draw(meshes, materials, m);
 }
 
-Model::Model(const std::string &path, GLuint progId): progId(progId) {
+Model::Model(const std::string &path, Program p): program(p) {
 	const aiScene *scene = importer.ReadFile(path, 
 			aiProcess_Triangulate | aiProcess_CalcTangentSpace | aiProcess_GenNormals);
 	if (!scene) {
@@ -142,18 +142,19 @@ Model::Model(const std::string &path, GLuint progId): progId(progId) {
 
 	for (int i = 0; i < scene->mNumMeshes; i++) {
 		const aiMesh *mesh = scene->mMeshes[i];
-		meshes.push_back(Mesh(mesh, progId));
+		meshes.push_back(Mesh(mesh, p.progId));
 	}
 
 	for (unsigned int i = 0; i < scene->mNumMaterials; i++) {
 		const aiMaterial &material = *scene->mMaterials[i];
-		materials.push_back(Material(material, progId));
+		materials.push_back(Material(material, p.progId));
 	}
 
-	root = new Node(*(scene->mRootNode), progId);
+	root = new Node(*(scene->mRootNode), p.progId);
 }
 
 void Model::draw() const {
+	glUseProgram(program.progId);
 	root->draw(meshes, materials);
 }
 
diff --git a/model.hpp b/model.hpp
index a39c70a..de8e27f 100644
--- a/model.hpp
+++ b/model.hpp
@@ -8,6 +8,7 @@
 #include <assimp/scene.h>
 #include <assimp/Importer.hpp>
 #include "material.hpp"
+#include "program.hpp"
 
 class Model {
 
@@ -18,7 +19,7 @@ class Model {
 	};
 	
 	public:
-		Model(const std::string &path, GLuint progId);
+		Model(const std::string &path, Program p);
 		void draw() const;
 
 		class Node {
@@ -40,7 +41,7 @@ class Model {
 		Node* find(const std::string &name);
 	
 	private:
-		const GLuint progId;
+		const Program program;
 		
 		std::vector<Mesh> meshes;
 		Node *root;
diff --git a/models/skybox/back.jpg b/models/skybox/back.jpg
new file mode 100755
index 0000000..470a679
Binary files /dev/null and b/models/skybox/back.jpg differ
diff --git a/models/skybox/bottom.jpg b/models/skybox/bottom.jpg
new file mode 100755
index 0000000..893f394
Binary files /dev/null and b/models/skybox/bottom.jpg differ
diff --git a/models/skybox/front.jpg b/models/skybox/front.jpg
new file mode 100755
index 0000000..4e17b77
Binary files /dev/null and b/models/skybox/front.jpg differ
diff --git a/models/skybox/left.jpg b/models/skybox/left.jpg
new file mode 100755
index 0000000..5750b91
Binary files /dev/null and b/models/skybox/left.jpg differ
diff --git a/models/skybox/right.jpg b/models/skybox/right.jpg
new file mode 100755
index 0000000..8963037
Binary files /dev/null and b/models/skybox/right.jpg differ
diff --git a/models/skybox/top.jpg b/models/skybox/top.jpg
new file mode 100755
index 0000000..4db3c2a
Binary files /dev/null and b/models/skybox/top.jpg differ
diff --git a/program.cpp b/program.cpp
new file mode 100644
index 0000000..b1f2ede
--- /dev/null
+++ b/program.cpp
@@ -0,0 +1,50 @@
+#include "program.hpp"
+#include <fstream>
+#include <sstream>
+#include <iostream>
+
+using namespace std;
+
+void attachShader(GLuint progId, string filePath, GLenum type) {
+	GLuint shader = glCreateShader(type);
+
+	if (!shader) {
+		cerr << "error creating shader" << endl;
+		exit(1);
+	}
+
+	ifstream file(filePath);
+	stringstream buffer;
+	buffer << file.rdbuf();
+	string str = buffer.str();
+	const char* contents = str.c_str();
+
+	glShaderSource(shader, 1, (const GLchar**)&contents, NULL);
+	glCompileShader(shader);
+	GLint success;
+	glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
+	if (!success) {
+		GLchar log[1024];
+		glGetShaderInfoLog(shader, 1024, NULL, log);
+		fprintf(stderr, "error: %s\n", log);
+		exit(1);
+	}
+	glAttachShader(progId, shader);
+}
+
+Program::Program(const string vertexShader, const string fragmentShader) {
+	progId = glCreateProgram();
+
+	attachShader(progId, vertexShader, GL_VERTEX_SHADER);
+	attachShader(progId, fragmentShader, GL_FRAGMENT_SHADER);
+
+	glLinkProgram(progId);
+	GLint success = 0;
+	glGetProgramiv(progId, GL_LINK_STATUS, &success);
+	if (!success) {
+		GLchar log[1024];
+		glGetProgramInfoLog(progId, sizeof(log), NULL, log);
+		fprintf(stderr, "error linking: %s\n", log);
+		exit(1);
+	}
+}
diff --git a/program.hpp b/program.hpp
new file mode 100644
index 0000000..0436338
--- /dev/null
+++ b/program.hpp
@@ -0,0 +1,10 @@
+#ifndef PROGRAM_HPP
+#define PROGRAM_HPP
+#include <string>
+#include <GL/glew.h>
+class Program {
+	public:
+		Program(const std::string vert, const std::string frag);
+		GLuint progId;
+};
+#endif
diff --git a/shapes.hpp b/shapes.hpp
new file mode 100644
index 0000000..69520aa
--- /dev/null
+++ b/shapes.hpp
@@ -0,0 +1,84 @@
+#include <array>
+#define GLM_FORCE_PURE
+#include <glm/glm.hpp>
+
+using namespace std;
+
+constexpr array<glm::vec3, 6> quadToTriangles(const array<glm::vec3, 4> quads) {
+	return {
+		quads[0],
+		quads[1],
+		quads[2],
+		quads[2],
+		quads[3],
+		quads[0]
+	};
+}
+
+constexpr const glm::vec3 foo() {
+	constexpr glm::vec3 foo(1,2,3);
+	return foo;
+}
+
+constexpr array<glm::vec3, 36> cube() {
+	int i = 0;
+	array<glm::vec3, 36> vertices;
+	
+	const array<glm::vec3, 4> front = {
+		glm::vec3(1, -1, -1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(-1, 1, -1),
+		glm::vec3(1, 1, -1)
+	};
+	
+	for (auto v: quadToTriangles(front))
+		vertices[i++] = v;
+
+	const array<glm::vec3, 4> back = {
+		glm::vec3(1, 1, 1),
+		glm::vec3(-1, 1, 1),
+		glm::vec3(-1, -1, 1),
+		glm::vec3(1, -1, 1)
+	};
+	for (auto v: quadToTriangles(back))
+		vertices[i++] = v;
+
+
+	const array<glm::vec3, 4> top = {
+		glm::vec3(1, 1, -1),
+		glm::vec3(-1, 1, -1),
+		glm::vec3(-1, 1, 1),
+		glm::vec3(1, 1, 1)
+	};
+	for (auto v: quadToTriangles(top))
+		vertices[i++] = v;
+
+	const array<glm::vec3, 4> bottom = {
+		glm::vec3(1, -1, 1),
+		glm::vec3(-1, -1, 1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(1, -1, -1)
+	};
+	for (auto v: quadToTriangles(bottom))
+		vertices[i++] = v;
+
+	const array<glm::vec3, 4> left = {
+		glm::vec3(-1, 1, 1),
+		glm::vec3(-1, 1, -1),
+		glm::vec3(-1, -1, -1),
+		glm::vec3(-1, -1, 1)
+	};
+	for (auto v: quadToTriangles(left))
+		vertices[i++] = v;
+
+	const array<glm::vec3, 4> right = {
+		glm::vec3(1, 1, -1),
+		glm::vec3(1, 1, 1),
+		glm::vec3(1, -1, 1),
+		glm::vec3(1, -1, -1)
+	};
+	for (auto v: quadToTriangles(right))
+		vertices[i++] = v;
+
+	return vertices;
+}
diff --git a/skybox.cpp b/skybox.cpp
new file mode 100644
index 0000000..bd097cb
--- /dev/null
+++ b/skybox.cpp
@@ -0,0 +1,72 @@
+#include "shapes.hpp"
+#include "skybox.hpp"
+#include "image.hpp"
+#include <GL/glew.h>
+#include <glm/gtc/type_ptr.hpp>
+	
+Skybox::Skybox(const std::vector<std::string> faces): program("skyboxvert.glsl", "skyboxfrag.glsl") {
+	glUseProgram(program.progId);
+	glGenTextures(1, &texId);
+	glBindTexture(GL_TEXTURE_CUBE_MAP, texId);
+
+	int width, height, numChans;
+	for (int i = 0; i < faces.size(); i++) {
+		Image img(faces[i]);
+
+		glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGBA, img.width(), img.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img.data());
+	}
+
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+	glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
+
+	glGenVertexArrays(1, &vao);
+	glBindVertexArray(vao);
+
+	GLuint vbo;
+	glGenBuffers(1, &vbo);
+
+	auto vertices = cube();
+
+	glBindBuffer(GL_ARRAY_BUFFER, vbo);
+	glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(glm::vec3), &vertices[0], GL_STATIC_DRAW);
+	
+	GLuint posLoc = glGetAttribLocation(program.progId, "pos");
+	glEnableVertexAttribArray(posLoc);
+	glVertexAttribPointer(posLoc, 3, GL_FLOAT, GL_FALSE, 0, 0);
+}
+void validatePrograms(GLuint progId) {
+	glValidateProgram(progId);
+	
+	GLint success;
+	glGetProgramiv(progId, GL_VALIDATE_STATUS, &success);
+	if (!success) {
+		GLchar log[1024];
+		glGetProgramInfoLog(progId, sizeof(log), NULL, log);
+		fprintf(stderr, "error: %s\n", log);
+		exit(1);
+	}
+}
+
+void Skybox::draw(glm::mat4 proj, glm::mat4 view) const {
+	glUseProgram(program.progId);
+
+	glDepthMask(GL_FALSE);
+	glDisable(GL_CULL_FACE);
+	glBindVertexArray(vao);
+	validatePrograms(program.progId);
+
+	GLuint projLoc = glGetUniformLocation(program.progId, "projection");
+	glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(proj));
+
+	GLuint viewLoc = glGetUniformLocation(program.progId, "view");
+	view = glm::mat4(glm::mat3(view));
+	glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
+
+	glBindTexture(GL_TEXTURE_CUBE_MAP, texId);
+	glDrawArrays(GL_TRIANGLES, 0, 36);
+	glEnable(GL_CULL_FACE);
+	glDepthMask(GL_TRUE);
+}
diff --git a/skybox.hpp b/skybox.hpp
new file mode 100644
index 0000000..f1ac4ee
--- /dev/null
+++ b/skybox.hpp
@@ -0,0 +1,13 @@
+#include <string>
+#include <vector>
+#include <GL/glew.h>
+#include <glm/glm.hpp>
+#include "program.hpp"
+class Skybox {
+	public:
+		Skybox(const std::vector<std::string> faces);
+		void draw(glm::mat4 proj, glm::mat4 view) const;
+	private:
+		GLuint texId, vao;
+		const Program program;
+};
diff --git a/skyboxfrag.glsl b/skyboxfrag.glsl
new file mode 100644
index 0000000..90c7ebe
--- /dev/null
+++ b/skyboxfrag.glsl
@@ -0,0 +1,10 @@
+#version 330
+
+in vec3 texCoords;
+out vec4 fragColor;
+
+uniform samplerCube skybox;
+
+void main() {
+	fragColor = texture(skybox, texCoords);
+}
diff --git a/skyboxvert.glsl b/skyboxvert.glsl
new file mode 100644
index 0000000..f1ba729
--- /dev/null
+++ b/skyboxvert.glsl
@@ -0,0 +1,12 @@
+#version 330
+
+in vec3 pos;
+out vec3 texCoords;
+
+uniform mat4 projection;
+uniform mat4 view;
+
+void main() {
+	texCoords = pos;
+	gl_Position = projection * view * vec4(pos, 1);
+}