X-Git-Url: http://git.lukelau.me/?p=opengl.git;a=blobdiff_plain;f=main.cpp;h=67c3ebeeae849482ba27d7ea0f9be79cd76c70f7;hp=4cc4280be0180f5f44d86e7c426a99c8a7d2d771;hb=c5d984e4904ae7b286bf095a1c640cc25cebe9be;hpb=f26de7de42a3d0a52365de79f528fcea808e2bca

diff --git a/main.cpp b/main.cpp
index 4cc4280..67c3ebe 100644
--- a/main.cpp
+++ b/main.cpp
@@ -19,20 +19,15 @@
 
 using namespace std;
 
-GLuint* vaos;
-GLuint progId;
+GLuint pyramidVao, lightVao;
+GLuint gradientProgId, solidProgId;
 glm::vec3 camPos   = glm::vec3(0.0f, 0.0f,  -5.0f);
 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;
 
-void display() {
-	glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
-	glUseProgram(progId);
-	glBindVertexArray(vaos[0]);
-	for (int i = 0; i < 100; i++) {
-
+void setProjectionAndViewUniforms(GLuint progId) {
 	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));
@@ -40,12 +35,42 @@ void display() {
 	GLuint viewId = glGetUniformLocation(progId, "view");
 	glm::mat4 view = glm::lookAt(camPos, camPos + camFront, camUp);
 	glUniformMatrix4fv(viewId, 1, GL_FALSE, glm::value_ptr(view));
+}
+
+void drawLight(float d, glm::vec3 lightPos) {
+  	glUseProgram(solidProgId);
+	glBindVertexArray(lightVao);
+	setProjectionAndViewUniforms(solidProgId);
+	glm::mat4 model = glm::translate(glm::mat4(1.f), lightPos);
+	model = glm::scale(model, glm::vec3(0.2));
+	GLuint modelId = glGetUniformLocation(solidProgId, "model");
+	glUniformMatrix4fv(modelId, 1, GL_FALSE, glm::value_ptr(model));
+
+	GLuint colorLoc = glGetUniformLocation(solidProgId, "color");
+	glm::vec3 color = glm::vec3(1, 1, 1);
+	glUniform3fv(colorLoc, 1, glm::value_ptr(color));
+		
+	glDrawArrays(GL_TRIANGLES, 0, 36);
+};
+
+void drawPyramids(float d, glm::vec3 lightPos) {
+	glUseProgram(gradientProgId);
+	glBindVertexArray(pyramidVao);
+	setProjectionAndViewUniforms(gradientProgId);
+
+	GLuint lightPosLoc = glGetUniformLocation(gradientProgId, "lightPos");
+	glUniform3fv(lightPosLoc, 1, glm::value_ptr(lightPos));
+	
+	GLuint viewPosLoc = glGetUniformLocation(gradientProgId, "viewPos");
+	glUniform3fv(viewPosLoc, 1, glm::value_ptr(camPos));
+
+	GLuint modelId = glGetUniformLocation(gradientProgId, "model");
+
+	for (int i = 0; i < 10; i++) {
 
-		GLuint modelId = glGetUniformLocation(progId, "model");
 		glm::mat4 model = glm::mat4(1.f);
 
-		float d = (float)glutGet(GLUT_ELAPSED_TIME) * 0.001f;
-		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 +86,20 @@ void display() {
 
 		glUniformMatrix4fv(modelId, 1, GL_FALSE, glm::value_ptr(model));
 		
-		glDrawArrays(GL_TRIANGLES, 0, 12);
+		glDrawArrays(GL_TRIANGLES, 0, 18);
 	}
+
+};
+
+void display() {
+	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, 0, cos(d) * 10);
+
+	drawPyramids(d, lightPos);
+	drawLight(d, lightPos);
+
 	glutSwapBuffers();
 }
 
@@ -114,7 +151,7 @@ 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 +166,20 @@ 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 +189,118 @@ 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 validateProgram(GLuint progId) {
 	glValidateProgram(progId);
 	
@@ -178,33 +315,57 @@ 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,
-
-		-1.0f, -1.0f, 1.0f,
-		1.0f, -1.0f, 1.0f,
-		0.0f, 1.0f, 0.0f,
-
-		-1.0f, -1.0f, -1.0f,
-		-1.0f, -1.0f, 1.0f,
-		0.0f, 1.0f, 0.0f,
-
-		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)
 	};
 
-	vaos = new GLuint[2];
+	// 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*)"fragment.glsl");
+	glUseProgram(gradientProgId);
+	pyramidVao = setupBuffers(vertices, normals, gradientProgId);
+	validateProgram(gradientProgId);
 
-	progId = compileShaders((char*)"vertex.glsl", (char*)"fragment.glsl");
-	glUseProgram(progId);
-	vaos[0] = setupBuffers(vertices, progId);
-	validateProgram(progId);
+	solidProgId = compileShaders((char*)"solidvertex.glsl", (char*)"solidfrag.glsl");
+	glUseProgram(solidProgId);
+	setupLightBuffers(solidProgId);
+	validateProgram(solidProgId);
 
 	glEnable(GL_DEPTH_TEST); 
+	glEnable(GL_CULL_FACE); 
 }
 
 bool* keyStates = new bool[256];