5 #include <glm/gtc/type_ptr.hpp>
7 Skybox::Skybox(const std::vector<std::string> faces): program("skyboxvert.glsl", "skyboxfrag.glsl") {
8 glUseProgram(program.progId);
9 glGenTextures(1, &texId);
10 glBindTexture(GL_TEXTURE_CUBE_MAP, texId);
12 int width, height, numChans;
13 for (int i = 0; i < faces.size(); i++) {
16 glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X + i, 0, GL_RGBA, img.width(), img.height(), 0, GL_RGBA, GL_UNSIGNED_BYTE, img.data());
19 glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
20 glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
21 glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
22 glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
23 glTexParameteri(GL_TEXTURE_CUBE_MAP, GL_TEXTURE_WRAP_R, GL_CLAMP_TO_EDGE);
25 glGenVertexArrays(1, &vao);
26 glBindVertexArray(vao);
29 glGenBuffers(1, &vbo);
31 auto vertices = cube();
33 glBindBuffer(GL_ARRAY_BUFFER, vbo);
34 glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(glm::vec3), &vertices[0], GL_STATIC_DRAW);
36 GLuint posLoc = glGetAttribLocation(program.progId, "pos");
37 glEnableVertexAttribArray(posLoc);
38 glVertexAttribPointer(posLoc, 3, GL_FLOAT, GL_FALSE, 0, 0);
40 void validatePrograms(GLuint progId) {
41 glValidateProgram(progId);
44 glGetProgramiv(progId, GL_VALIDATE_STATUS, &success);
47 glGetProgramInfoLog(progId, sizeof(log), NULL, log);
48 fprintf(stderr, "error: %s\n", log);
53 void Skybox::draw(glm::mat4 proj, glm::mat4 view) const {
54 glUseProgram(program.progId);
56 glDepthMask(GL_FALSE);
57 glDisable(GL_CULL_FACE);
58 glBindVertexArray(vao);
59 validatePrograms(program.progId);
61 GLuint projLoc = glGetUniformLocation(program.progId, "projection");
62 glUniformMatrix4fv(projLoc, 1, GL_FALSE, glm::value_ptr(proj));
64 GLuint viewLoc = glGetUniformLocation(program.progId, "view");
65 view = glm::mat4(glm::mat3(view));
66 glUniformMatrix4fv(viewLoc, 1, GL_FALSE, glm::value_ptr(view));
68 glBindTexture(GL_TEXTURE_CUBE_MAP, texId);
69 glDrawArrays(GL_TRIANGLES, 0, 36);
70 glEnable(GL_CULL_FACE);