pixwerx/src/deps/tinygltfloader-0.9.2/examples/glview/glview.cc

546 lines
16 KiB
C++

#include <vector>
#include <string>
#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <limits>
#include <cassert>
#include <cmath>
#include <GL/glew.h>
#define GLFW_INCLUDE_GLU
#include <GLFW/glfw3.h>
#include "trackball.h"
#define TINYGLTF_LOADER_IMPLEMENTATION
#define STB_IMAGE_IMPLEMENTATION
#include "tiny_gltf_loader.h"
#define BUFFER_OFFSET(i) ((char *)NULL + (i))
#define CheckGLErrors(desc) \
{ \
GLenum e = glGetError(); \
if (e != GL_NO_ERROR) { \
printf("OpenGL error in \"%s\": %d (%d) %s:%d\n", desc, e, e, __FILE__, \
__LINE__); \
exit(20); \
} \
}
#define CAM_Z (3.0f)
int width = 768;
int height = 768;
double prevMouseX, prevMouseY;
bool mouseLeftPressed;
bool mouseMiddlePressed;
bool mouseRightPressed;
float curr_quat[4];
float prev_quat[4];
float eye[3], lookat[3], up[3];
GLFWwindow *window;
typedef struct { GLuint vb; } GLBufferState;
typedef struct {
std::vector<GLuint> diffuseTex; // for each primitive in mesh
} GLMeshState;
typedef struct {
std::map<std::string, GLint> attribs;
std::map<std::string, GLint> uniforms;
} GLProgramState;
std::map<std::string, GLBufferState> gBufferState;
std::map<std::string, GLMeshState> gMeshState;
GLProgramState gGLProgramState;
void CheckErrors(std::string desc) {
GLenum e = glGetError();
if (e != GL_NO_ERROR) {
fprintf(stderr, "OpenGL error in \"%s\": %d (%d)\n", desc.c_str(), e, e);
exit(20);
}
}
bool LoadShader(GLenum shaderType, // GL_VERTEX_SHADER or GL_FRAGMENT_SHADER(or
// maybe GL_COMPUTE_SHADER)
GLuint &shader, const char *shaderSourceFilename) {
GLint val = 0;
// free old shader/program
if (shader != 0) {
glDeleteShader(shader);
}
std::vector<GLchar> srcbuf;
FILE *fp = fopen(shaderSourceFilename, "rb");
if (!fp) {
fprintf(stderr, "failed to load shader: %s\n", shaderSourceFilename);
return false;
}
fseek(fp, 0, SEEK_END);
size_t len = ftell(fp);
rewind(fp);
srcbuf.resize(len + 1);
len = fread(&srcbuf.at(0), 1, len, fp);
srcbuf[len] = 0;
fclose(fp);
const GLchar *srcs[1];
srcs[0] = &srcbuf.at(0);
shader = glCreateShader(shaderType);
glShaderSource(shader, 1, srcs, NULL);
glCompileShader(shader);
glGetShaderiv(shader, GL_COMPILE_STATUS, &val);
if (val != GL_TRUE) {
char log[4096];
GLsizei msglen;
glGetShaderInfoLog(shader, 4096, &msglen, log);
printf("%s\n", log);
// assert(val == GL_TRUE && "failed to compile shader");
printf("ERR: Failed to load or compile shader [ %s ]\n",
shaderSourceFilename);
return false;
}
printf("Load shader [ %s ] OK\n", shaderSourceFilename);
return true;
}
bool LinkShader(GLuint &prog, GLuint &vertShader, GLuint &fragShader) {
GLint val = 0;
if (prog != 0) {
glDeleteProgram(prog);
}
prog = glCreateProgram();
glAttachShader(prog, vertShader);
glAttachShader(prog, fragShader);
glLinkProgram(prog);
glGetProgramiv(prog, GL_LINK_STATUS, &val);
assert(val == GL_TRUE && "failed to link shader");
printf("Link shader OK\n");
return true;
}
void reshapeFunc(GLFWwindow *window, int w, int h) {
glViewport(0, 0, w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0, (float)w / (float)h, 0.1f, 1000.0f);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
width = w;
height = h;
}
void keyboardFunc(GLFWwindow *window, int key, int scancode, int action,
int mods) {
if (action == GLFW_PRESS || action == GLFW_REPEAT) {
// Close window
if (key == GLFW_KEY_Q || key == GLFW_KEY_ESCAPE)
glfwSetWindowShouldClose(window, GL_TRUE);
}
}
void clickFunc(GLFWwindow *window, int button, int action, int mods) {
double x, y;
glfwGetCursorPos(window, &x, &y);
if (button == GLFW_MOUSE_BUTTON_LEFT) {
mouseLeftPressed = true;
if (action == GLFW_PRESS) {
int id = -1;
// int id = ui.Proc(x, y);
if (id < 0) { // outside of UI
trackball(prev_quat, 0.0, 0.0, 0.0, 0.0);
}
} else if (action == GLFW_RELEASE) {
mouseLeftPressed = false;
}
}
if (button == GLFW_MOUSE_BUTTON_RIGHT) {
if (action == GLFW_PRESS) {
mouseRightPressed = true;
} else if (action == GLFW_RELEASE) {
mouseRightPressed = false;
}
}
if (button == GLFW_MOUSE_BUTTON_MIDDLE) {
if (action == GLFW_PRESS) {
mouseMiddlePressed = true;
} else if (action == GLFW_RELEASE) {
mouseMiddlePressed = false;
}
}
}
void motionFunc(GLFWwindow *window, double mouse_x, double mouse_y) {
float rotScale = 1.0f;
float transScale = 2.0f;
if (mouseLeftPressed) {
trackball(prev_quat, rotScale * (2.0f * prevMouseX - width) / (float)width,
rotScale * (height - 2.0f * prevMouseY) / (float)height,
rotScale * (2.0f * mouse_x - width) / (float)width,
rotScale * (height - 2.0f * mouse_y) / (float)height);
add_quats(prev_quat, curr_quat, curr_quat);
} else if (mouseMiddlePressed) {
eye[0] += -transScale * (mouse_x - prevMouseX) / (float)width;
lookat[0] += -transScale * (mouse_x - prevMouseX) / (float)width;
eye[1] += transScale * (mouse_y - prevMouseY) / (float)height;
lookat[1] += transScale * (mouse_y - prevMouseY) / (float)height;
} else if (mouseRightPressed) {
eye[2] += transScale * (mouse_y - prevMouseY) / (float)height;
lookat[2] += transScale * (mouse_y - prevMouseY) / (float)height;
}
// Update mouse point
prevMouseX = mouse_x;
prevMouseY = mouse_y;
}
static void SetupGLState(Scene &scene, GLuint progId) {
// Buffer
{
std::map<std::string, BufferView>::const_iterator it(
scene.bufferViews.begin());
std::map<std::string, BufferView>::const_iterator itEnd(
scene.bufferViews.end());
for (; it != itEnd; it++) {
const BufferView &bufferView = it->second;
if (bufferView.target == 0) {
continue; // Unsupported bufferView.
}
const Buffer &buffer = scene.buffers[bufferView.buffer];
GLBufferState state;
glGenBuffers(1, &state.vb);
glBindBuffer(bufferView.target, state.vb);
glBufferData(bufferView.target, bufferView.byteLength,
&buffer.data.at(0) + bufferView.byteOffset, GL_STATIC_DRAW);
glBindBuffer(bufferView.target, 0);
gBufferState[it->first] = state;
}
}
// Texture
{
std::map<std::string, Mesh>::const_iterator it(scene.meshes.begin());
std::map<std::string, Mesh>::const_iterator itEnd(scene.meshes.end());
for (; it != itEnd; it++) {
const Mesh &mesh = it->second;
gMeshState[mesh.name].diffuseTex.resize(mesh.primitives.size());
for (size_t primId = 0; primId < mesh.primitives.size(); primId++) {
const Primitive &primitive = mesh.primitives[primId];
gMeshState[mesh.name].diffuseTex[primId] = 0;
if (primitive.material.empty()) {
continue;
}
Material &mat = scene.materials[primitive.material];
printf("material.name = %s\n", mat.name.c_str());
if (mat.values.find("diffuse") != mat.values.end()) {
std::string diffuseTexName = mat.values["diffuse"].stringValue;
if (scene.textures.find(diffuseTexName) != scene.textures.end()) {
Texture &tex = scene.textures[diffuseTexName];
if (scene.images.find(tex.source) != scene.images.end()) {
Image &image = scene.images[tex.source];
GLuint texId;
glGenTextures(1, &texId);
glBindTexture(tex.target, texId);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexParameterf(tex.target, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameterf(tex.target, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
// Ignore Texture.fomat.
GLenum format = GL_RGBA;
if (image.component == 3) {
format = GL_RGB;
}
glTexImage2D(tex.target, 0, tex.internalFormat, image.width,
image.height, 0, format, tex.type,
&image.image.at(0));
CheckErrors("texImage2D");
glBindTexture(tex.target, 0);
printf("TexId = %d\n", texId);
gMeshState[mesh.name].diffuseTex[primId] = texId;
}
}
}
}
}
}
glUseProgram(progId);
GLint vtloc = glGetAttribLocation(progId, "in_vertex");
GLint nrmloc = glGetAttribLocation(progId, "in_normal");
GLint uvloc = glGetAttribLocation(progId, "in_texcoord");
GLint diffuseTexLoc = glGetUniformLocation(progId, "diffuseTex");
gGLProgramState.attribs["POSITION"] = vtloc;
gGLProgramState.attribs["NORMAL"] = nrmloc;
gGLProgramState.attribs["TEXCOORD_0"] = uvloc;
gGLProgramState.uniforms["diffuseTex"] = diffuseTexLoc;
};
void DrawMesh(Scene &scene, const Mesh &mesh) {
if (gGLProgramState.uniforms["diffuseTex"] >= 0) {
glUniform1i(gGLProgramState.uniforms["diffuseTex"], 0); // TEXTURE0
}
for (size_t i = 0; i < mesh.primitives.size(); i++) {
const Primitive &primitive = mesh.primitives[i];
if (primitive.indices.empty())
return;
std::map<std::string, std::string>::const_iterator it(
primitive.attributes.begin());
std::map<std::string, std::string>::const_iterator itEnd(
primitive.attributes.end());
// Assume TEXTURE_2D target for the texture object.
glBindTexture(GL_TEXTURE_2D, gMeshState[mesh.name].diffuseTex[i]);
for (; it != itEnd; it++) {
const Accessor &accessor = scene.accessors[it->second];
glBindBuffer(GL_ARRAY_BUFFER, gBufferState[accessor.bufferView].vb);
CheckErrors("bind buffer");
int count = 1;
if (accessor.type == TINYGLTF_TYPE_SCALAR) {
count = 1;
} else if (accessor.type == TINYGLTF_TYPE_VEC2) {
count = 2;
} else if (accessor.type == TINYGLTF_TYPE_VEC3) {
count = 3;
} else if (accessor.type == TINYGLTF_TYPE_VEC4) {
count = 4;
}
// it->first would be "POSITION", "NORMAL", "TEXCOORD_0", ...
if ((it->first.compare("POSITION") == 0) ||
(it->first.compare("NORMAL") == 0) ||
(it->first.compare("TEXCOORD_0") == 0)) {
glVertexAttribPointer(
gGLProgramState.attribs[it->first], count, accessor.componentType,
GL_FALSE, accessor.byteStride, BUFFER_OFFSET(accessor.byteOffset));
CheckErrors("vertex attrib pointer");
glEnableVertexAttribArray(gGLProgramState.attribs[it->first]);
CheckErrors("enable vertex attrib array");
}
}
const Accessor &indexAccessor = scene.accessors[primitive.indices];
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,
gBufferState[indexAccessor.bufferView].vb);
CheckErrors("bind buffer");
int mode = -1;
if (primitive.mode == TINYGLTF_MODE_TRIANGLES) {
mode = GL_TRIANGLES;
} else if (primitive.mode == TINYGLTF_MODE_TRIANGLE_STRIP) {
mode = GL_TRIANGLE_STRIP;
} else if (primitive.mode == TINYGLTF_MODE_TRIANGLE_FAN) {
mode = GL_TRIANGLE_FAN;
} else if (primitive.mode == TINYGLTF_MODE_POINTS) {
mode = GL_POINTS;
} else if (primitive.mode == TINYGLTF_MODE_LINE) {
mode = GL_LINES;
} else if (primitive.mode == TINYGLTF_MODE_LINE_LOOP) {
mode = GL_LINE_LOOP;
};
glDrawElements(mode, indexAccessor.count, indexAccessor.componentType,
BUFFER_OFFSET(indexAccessor.byteOffset));
CheckErrors("draw elements");
{
std::map<std::string, std::string>::const_iterator it(
primitive.attributes.begin());
std::map<std::string, std::string>::const_iterator itEnd(
primitive.attributes.end());
for (; it != itEnd; it++) {
if ((it->first.compare("POSITION") == 0) ||
(it->first.compare("NORMAL") == 0) ||
(it->first.compare("TEXCOORD_0") == 0)) {
glDisableVertexAttribArray(gGLProgramState.attribs[it->first]);
}
}
}
}
}
void DrawScene(Scene &scene) {
std::map<std::string, Mesh>::const_iterator it(scene.meshes.begin());
std::map<std::string, Mesh>::const_iterator itEnd(scene.meshes.end());
for (; it != itEnd; it++) {
DrawMesh(scene, it->second);
}
}
static void Init() {
trackball(curr_quat, 0, 0, 0, 0);
eye[0] = 0.0f;
eye[1] = 0.0f;
eye[2] = CAM_Z;
lookat[0] = 0.0f;
lookat[1] = 0.0f;
lookat[2] = 0.0f;
up[0] = 0.0f;
up[1] = 1.0f;
up[2] = 0.0f;
}
int main(int argc, char **argv) {
if (argc < 2) {
std::cout << "glview input.gltf <scale>\n" << std::endl;
return 0;
}
float scale = 1.0f;
if (argc > 2) {
scale = atof(argv[2]);
}
Scene scene;
TinyGLTFLoader loader;
std::string err;
bool ret = loader.LoadFromFile(scene, err, argv[1]);
if (!err.empty()) {
printf("ERR: %s\n", err.c_str());
}
if (!ret) {
printf("Failed to load .glTF : %s\n", argv[1]);
exit(-1);
}
Init();
if (!glfwInit()) {
std::cerr << "Failed to initialize GLFW." << std::endl;
return -1;
}
window = glfwCreateWindow(width, height, "Simple glTF geometry viewer", NULL,
NULL);
if (window == NULL) {
std::cerr << "Failed to open GLFW window. " << std::endl;
glfwTerminate();
return 1;
}
glfwGetWindowSize(window, &width, &height);
glfwMakeContextCurrent(window);
// Callback
glfwSetWindowSizeCallback(window, reshapeFunc);
glfwSetKeyCallback(window, keyboardFunc);
glfwSetMouseButtonCallback(window, clickFunc);
glfwSetCursorPosCallback(window, motionFunc);
glewExperimental = true;
if (glewInit() != GLEW_OK) {
std::cerr << "Failed to initialize GLEW." << std::endl;
return -1;
}
reshapeFunc(window, width, height);
GLuint vertId = 0, fragId = 0, progId = 0;
if (false == LoadShader(GL_VERTEX_SHADER, vertId, "shader.vert")) {
return -1;
}
CheckErrors("load vert shader");
if (false == LoadShader(GL_FRAGMENT_SHADER, fragId, "shader.frag")) {
return -1;
}
CheckErrors("load frag shader");
if (false == LinkShader(progId, vertId, fragId)) {
return -1;
}
CheckErrors("link");
{
GLint vtxLoc = glGetAttribLocation(progId, "in_vertex");
if (vtxLoc < 0) {
printf("vertex loc not found.\n");
exit(-1);
}
GLint tnLoc = glGetAttribLocation(progId, "in_normal");
if (tnLoc < 0) {
printf("normal loc not found.\n");
exit(-1);
}
}
glUseProgram(progId);
CheckErrors("useProgram");
SetupGLState(scene, progId);
CheckErrors("SetupGLState");
while (glfwWindowShouldClose(window) == GL_FALSE) {
glfwPollEvents();
glClearColor(0.1f, 0.2f, 0.3f, 1.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glEnable(GL_DEPTH_TEST);
GLfloat mat[4][4];
build_rotmatrix(mat, curr_quat);
// camera(define it in projection matrix)
glMatrixMode(GL_PROJECTION);
glPushMatrix();
gluLookAt(eye[0], eye[1], eye[2], lookat[0], lookat[1], lookat[2], up[0],
up[1], up[2]);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glMultMatrixf(&mat[0][0]);
glScalef(scale, scale, scale);
DrawScene(scene);
glMatrixMode(GL_PROJECTION);
glPopMatrix();
glFlush();
glfwSwapBuffers(window);
}
glfwTerminate();
}