From 526f5c3dc0302e541c95ed2198ce8fdb5cdd0b99 Mon Sep 17 00:00:00 2001 From: Luke Lau Date: Thu, 11 Oct 2018 23:54:17 +0100 Subject: [PATCH] Add Phong lighting --- fragment.glsl | 15 +++++++++- main.cpp | 81 +++++++++++++++++++++++++++++++++++---------------- vertex.glsl | 8 ++++- 3 files changed, 77 insertions(+), 27 deletions(-) diff --git a/fragment.glsl b/fragment.glsl index edc4f63..e41a7f9 100644 --- a/fragment.glsl +++ b/fragment.glsl @@ -1,7 +1,20 @@ #version 330 in vec4 color; +in vec3 normal; +in vec3 fragPos; +uniform vec3 lightPos; +uniform vec3 viewPos; out vec4 FragColor; void main() { - FragColor = color; + float ambient = 0.1; + float specularStrength = 0.5; + vec3 lightDir = normalize(fragPos - lightPos); + float diffuse = max(0, dot(normal, lightDir)); + + vec3 viewDir = normalize(fragPos - viewPos); + vec3 reflectDir = reflect(-lightDir, normal); + float specular = pow(max(0, dot(viewDir, reflectDir)), 128); + + FragColor = (ambient + diffuse + specular) * color; } diff --git a/main.cpp b/main.cpp index 4cc4280..ef18bf2 100644 --- a/main.cpp +++ b/main.cpp @@ -31,7 +31,8 @@ void display() { glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT); glUseProgram(progId); glBindVertexArray(vaos[0]); - for (int i = 0; i < 100; i++) { + + float d = (float)glutGet(GLUT_ELAPSED_TIME) * 0.001f; GLuint projId = glGetUniformLocation(progId, "projection"); glm::mat4 proj = glm::perspective(glm::radians(45.f), 1.33f, 0.01f, 10000.f); @@ -41,11 +42,20 @@ void display() { glm::mat4 view = glm::lookAt(camPos, camPos + camFront, camUp); glUniformMatrix4fv(viewId, 1, GL_FALSE, glm::value_ptr(view)); + GLuint lightPosLoc = glGetUniformLocation(progId, "lightPos"); + glm::vec3 lightPos = glm::vec3(sin(d) * 10, 0, 0);//10 * cos(d)); + glUniform3fv(lightPosLoc, 1, glm::value_ptr(lightPos)); + + GLuint viewPosLoc = glGetUniformLocation(progId, "viewPos"); + glUniform3fv(viewPosLoc, 1, glm::value_ptr(camPos)); + GLuint modelId = glGetUniformLocation(progId, "model"); + + for (int i = 0; i < 10; i++) { + 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)); @@ -114,7 +124,7 @@ 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, @@ -144,22 +154,29 @@ 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; } @@ -178,33 +195,47 @@ 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[12] = { + 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) }; + // work out the normals + glm::vec3 normals[12]; + for (int i = 0; i < 4; 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); + } + } + vaos = new GLuint[2]; progId = compileShaders((char*)"vertex.glsl", (char*)"fragment.glsl"); glUseProgram(progId); - vaos[0] = setupBuffers(vertices, progId); + vaos[0] = setupBuffers(vertices, normals, progId); validateProgram(progId); glEnable(GL_DEPTH_TEST); + glEnable(GL_CULL_FACE); } bool* keyStates = new bool[256]; diff --git a/vertex.glsl b/vertex.glsl index 3bf0a48..e2d30b7 100644 --- a/vertex.glsl +++ b/vertex.glsl @@ -1,12 +1,18 @@ #version 330 in vec3 vPosition; in vec4 vColor; +in vec3 vNormal; uniform mat4 model; uniform mat4 view; uniform mat4 projection; out vec4 color; +out vec3 normal; +out vec3 fragPos; void main() { - gl_Position = projection * view * model * vec4(vPosition, 1.f); + vec4 pos = model * vec4(vPosition, 1.f); + gl_Position = projection * view * pos; + fragPos = vec3(pos); color = vColor; + normal = vNormal; } -- 2.30.2