X-Git-Url: https://git.lukelau.me/?p=opengl.git;a=blobdiff_plain;f=skybox.cpp;fp=skybox.cpp;h=bd097cb473dc85f92189a354325de78f6b4c4ba5;hp=0000000000000000000000000000000000000000;hb=c44e69ec78367fb2957324026894aef970f2481a;hpb=85f8f7278f24fe73fef1a19174376b155319072f

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);
+}