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4 Commits

Author SHA1 Message Date
c463904a6b lib: add mini tests framework 2024-10-14 22:40:35 +02:00
bca01fe3cd feat: add probe functions for user customization
custom probes inside the library allow the user developer
to run useful code along the renderer loop
2024-10-08 23:36:14 +02:00
950fb4d353 feat: introduce camera interface 2024-10-08 19:43:14 +02:00
5d19366642 fix: input handling 2024-10-08 17:27:09 +02:00
21 changed files with 864 additions and 748 deletions

12
INSTALL Normal file
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@ -0,0 +1,12 @@
+=============+
| INSTALL |
+=============+
DEBIAN PACKAGES
sudo apt-get update
sudo apt-get install libglew-dev
sudo apt-get install libglfw3-dev
sudo apt-get install libcglm-dev
sudo apt-get install libassimp-dev

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@ -1,23 +1,35 @@
CC=gcc
CFLAGS=-DFREEGLUT_STATIC -g3
CFLAGS=-DFREEGLUT -g3 -iquote include/
LFLAGS=-lglfw -L/usr/lib64 -lGLEW -lGL -lX11 -lGLU -lassimp -lm
LD=ld
OUT=build
DEV=dev.c
SRCDIR=src
BINDIR=build
TSTDIR=tests
all:
mkdir -p $(OUT)
$(CC) $(CFLAGS) -c rendlib.c -o $(OUT)/rendlib.o $(LFLAGS)
$(CC) $(CFLAGS) -c math.c -o $(OUT)/math.o $(LFLAGS)
$(CC) $(CFLAGS) -c object.c -o $(OUT)/object.o $(LFLAGS)
$(LD) -relocatable $(OUT)/rendlib.o $(OUT)/math.o $(OUT)/object.o -o $(OUT)/rendlib
LIB_SRCS = $(wildcard $(SRCDIR)/*.c)
LIB_OBJS = $(addprefix $(BINDIR)/, $(notdir $(LIB_SRCS:.c=.o)))
TST_SRCS = $(wildcard $(TSTDIR)/*.c)
TST_OBJS = $(addprefix $(BINDIR)/$(TSTDIR)/, $(notdir $(TST_SRCS:.c=.o)))
TST_ASST = $(shell find $(TSTDIR) -maxdepth 1 -mindepth 1 -type d)
dev: all
$(CC) $(CFLAGS) dev.c $(OUT)/rendlib -o $(OUT)/dev $(LFLAGS)
init:
mkdir -p $(BINDIR)
mkdir -p $(BINDIR)/tests
devall: dev
$(OUT)/dev
all: init $(LIB_OBJS)
$(LD) -relocatable $(LIB_OBJS) -o $(BINDIR)/rendlib
$(BINDIR)/%.o: $(SRCDIR)/%.c
$(CC) $(CFLAGS) -c $< -o $@ $(LFLAGS)
$(BINDIR)/$(TSTDIR)/test-%.o: $(TSTDIR)/test-%.c $(TSTDIR)/assets-% | all
$(CC) $(CFLAGS) $< $(BINDIR)/rendlib -o $@ $(LFLAGS)
cp -rf $(word 2,$^) $(BINDIR)/$(TSTDIR)/
test: $(TST_OBJS)
runt%: $(BINDIR)/$(TSTDIR)/test-%.o
cd $(BINDIR)/$(TSTDIR); ./test-$*.o
clean:
rm -rf $(OUT)
rm -rf $(BINDIR)

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@ -1,21 +0,0 @@
#version 330 core
in vec4 frag_pos;
in vec4 frag_normal;
in vec3 object_color;
out vec4 outy;
void main() {
vec4 norm = normalize(frag_normal);
vec4 ambient = vec4(0.7, 0.7788, 0.46, 1.0);
vec4 light_color = vec4(0.7, 0.7, 0.7, 1.0);
vec4 color = vec4(object_color.xyz, 1.0f);
vec4 light_location = vec4(0.0, 100.0, 0.0, 1.0);
vec4 light_direction = normalize(light_location - frag_pos);
float diff = max(dot(norm.xyz, light_direction.xyz), 0.0);
vec4 diffuse = diff * light_color;
outy = color + diffuse;
}

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@ -1,21 +0,0 @@
#version 330 core
layout (location = 0) in vec3 pos;
layout (location = 1) in vec3 normal;
uniform mat4 view;
uniform mat4 projection;
uniform mat4 translation;
uniform mat4 rotation;
uniform vec3 color;
uniform float scale;
out vec4 frag_pos;
out vec4 frag_normal;
out vec3 object_color;
void main() {
gl_Position = projection * view * translation * (vec4(pos.xyz, 1.0) * vec4(scale, scale, scale, 1.0));
frag_pos = gl_Position;
frag_normal = translation * vec4(normal.xyz, 1.0);
object_color = color;
}

34
dev.c
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@ -1,34 +0,0 @@
#include <stdlib.h>
#include <stdio.h>
#include "include/rendlib.h"
#include "include/object.h"
int main(int argc, char *argv[]) {
int ret = rendlib_start_window(argc, argv);
if (ret < 0) {
fprintf(stderr, "--error: %d\n", ret);
return EXIT_FAILURE;
}
struct model *m = load_model("assets/models/sphere.obj");
if (m == NULL) {
fprintf(stderr, "--error: loading model\n");
return EXIT_FAILURE;
}
struct object *o = create_object(&objects, 100.0f, m);
if (o == NULL) {
fprintf(stderr, "--error: creating object\n");
return EXIT_FAILURE;
}
ret = rendlib_render();
if (ret < 0) {
fprintf(stderr, "--error: %d\n", ret);
return EXIT_FAILURE;
}
fprintf(stdout, "--rendering\n");
return EXIT_SUCCESS;
}

14
include/batch.h Normal file
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@ -0,0 +1,14 @@
#ifndef BATCH_H
#define BATCH_H
#include <GL/glew.h>
struct batch {
int id;
GLint vertex_array;
GLint vertex_buffer;
GLint indices_buffer;
GLint normals_buffer;
};
#endif

32
include/camera.h Normal file
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@ -0,0 +1,32 @@
#ifndef CAMERA_H
#define CAMERA_H
#include <cglm/vec3.h>
#include <cglm/mat4.h>
#define CAMERA_PERSPECTIVE 0x1
#define CAMERA_ORTHOGRAPHIC 0x2
struct camera {
int type;
float fov;
float near_z;
float far_z;
float yaw;
float pitch;
float sensitivity;
float viewport_modifier;
vec3 pos;
vec3 front;
vec3 center;
vec3 up;
mat4 view;
mat4 projection;
};
struct camera *create_camera(int type);
int bake_camera(struct camera *c);
#endif

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@ -5,6 +5,5 @@
#include <cglm/cglm.h>
float frand48(void);
void calculate_gravity(struct object *src, struct object *target, vec3 force);
#endif

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@ -19,27 +19,19 @@ struct object {
vec4 translation_force;
vec4 position;
vec3 color;
float mass;
void *next;
float *paths;
int paths_num;
int paths_max;
struct model *model;
float scale;
unsigned int vao; // array object for the actual object
unsigned int vbo; // buffer for vertices
unsigned int ebo; // buffer for indices
unsigned int nbo; // buffer for normals
unsigned int pvao; // array object for paths
unsigned int pbo; // buffer for paths
unsigned int vao;
unsigned int vbo; // vertices
unsigned int ebo; // indices
unsigned int nbo; // normals
};
struct model *load_model(const char *path);
int record_path(struct object *obj);
struct object *create_object(struct object **o, float mass, struct model *model);
struct object *create_object(struct object **o, struct model *model);
#endif

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@ -8,7 +8,13 @@ enum errs {
err_shaders_init = -4,
};
extern struct camera *ac;
extern struct object *objects;
extern void (*keyboard_probe)(int key, int scancode, int action, int mods);
extern void (*mouse_probe)(double x, double y);
extern void (*update_probe)(void);
int rendlib_start_window(int argc, char *argv[]);
int rendlib_render(void);

48
include/shaders.h Normal file
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@ -0,0 +1,48 @@
#ifndef SHADERS_H
#define SHADERS_H
#define DEFAULT_VSHADER "#version 330 core\n" \
"layout (location = 0) in vec3 pos;\n" \
"layout (location = 1) in vec3 normal;\n" \
"\n" \
"uniform mat4 view;\n" \
"uniform mat4 projection;\n" \
"uniform mat4 translation;\n" \
"uniform mat4 rotation;\n" \
"uniform vec3 color;\n" \
"uniform float scale;\n" \
"\n" \
"out vec4 frag_pos;\n" \
"out vec4 frag_normal;\n" \
"out vec3 object_color;\n" \
"\n" \
"void main() {\n" \
" gl_Position = projection * view * translation * (vec4(pos.xyz, 1.0) * vec4(scale, scale, scale, 1.0));\n" \
" frag_pos = gl_Position;\n" \
" frag_normal = translation * vec4(normal.xyz, 1.0);\n" \
" object_color = color;\n" \
"}"
#define DEFAULT_FSHADER "#version 330 core\n" \
"in vec4 frag_pos;\n" \
"in vec4 frag_normal;\n" \
"in vec3 object_color;\n" \
"\n" \
"out vec4 outy;\n" \
"\n" \
"void main() {\n" \
" vec4 norm = normalize(frag_normal);\n" \
" vec4 ambient = vec4(0.7, 0.7788, 0.46, 1.0);\n" \
" vec4 light_color = vec4(0.7, 0.7, 0.7, 1.0);\n" \
" vec4 color = vec4(object_color.xyz, 1.0f);\n" \
"\n" \
" vec4 light_location = vec4(0.0, 100.0, 0.0, 1.0);\n" \
" vec4 light_direction = normalize(light_location - frag_pos);\n" \
" float diff = max(dot(norm.xyz, light_direction.xyz), 0.0);\n" \
"\n" \
" vec4 diffuse = diff * light_color;\n" \
"\n" \
" outy = color + diffuse;\n" \
"}"
#endif

42
math.c
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@ -1,42 +0,0 @@
#include "math.h"
#include "include/object.h"
#include <cglm/cglm.h>
float frand48(void) {
float number = (float) rand() / (float) (RAND_MAX + 1.0);
float side = rand() % 2;
if (side == 0) {
number = -number;
}
return number;
}
void calculate_gravity(struct object *src, struct object *target, vec3 force) {
vec4 v4distance;
glm_vec4_sub(target->position, src->position, v4distance);
vec3 v3distance;
glm_vec3(v4distance, v3distance);
float distance_xy = sqrt((v3distance[0] * v3distance[0]) + (v3distance[1] * v3distance[1]));
float distance_xyz = sqrt((distance_xy * distance_xy) + (v3distance[2] * v3distance[2]));
float force_scale = 4.0f;
float g = 6.67f * 1e-11f;
float top = g * src->mass * target->mass;
for (int i = 0; i < 3; i++) {
v3distance[i] = (v3distance[i] * v3distance[i] * v3distance[i]);
}
for (int i = 0; i < 3; i++) {
if (v3distance[i] == 0) {
force[i] = 0.0f;
continue;
}
force[i] = (top / (distance_xyz / (target->position[i] - src->position[i]))) * force_scale;
}
}

129
object.c
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@ -1,129 +0,0 @@
#include "include/object.h"
#include "include/math.h"
#include <math.h>
#include <assimp/cimport.h>
#include <assimp/scene.h>
#include <assimp/postprocess.h>
struct model *load_model(const char *path) {
struct model *new_model = (struct model *) calloc(1, sizeof(struct model));
const struct aiScene *scene = aiImportFile(path, aiProcess_Triangulate);
if (scene == NULL) {
fprintf(stderr, "Error: failed importing file from path '%s'", path);
}
for (int mesh_index = 0; mesh_index < scene->mNumMeshes; mesh_index++) {
struct aiMesh *mesh = scene->mMeshes[mesh_index];
// fetch vertices
for (int vertex_index = 0; vertex_index < mesh->mNumVertices; vertex_index++) {
struct aiVector3D *vertex = &(mesh->mVertices[vertex_index]);
long start = new_model->vertices_num*3;
new_model->vertices_num++;
new_model->vertices = (float *) realloc(new_model->vertices, new_model->vertices_num*3*sizeof(float));
if (new_model->vertices == NULL) {
fprintf(stderr, "Error: failed allocating memory for vertices\n");
goto error;
}
memcpy(&new_model->vertices[start], vertex, sizeof(float)*3);
}
// fetch indices
for (int face_index = 0; face_index < mesh->mNumFaces; face_index++) {
struct aiFace *face = &(mesh->mFaces[face_index]);
long start = new_model->indices_num;
new_model->indices_num += face->mNumIndices;
new_model->indices = (unsigned int *) realloc(new_model->indices, sizeof(unsigned int)*new_model->indices_num);
if (new_model->indices == NULL) {
fprintf(stderr, "Error: failed allocating memory for indices\n");
goto error;
}
memcpy(&new_model->indices[start], face->mIndices, sizeof(unsigned int)*face->mNumIndices);
}
// fetch normals
for (int normal_index = 0; normal_index < mesh->mNumVertices; normal_index++) {
struct aiVector3D *normal = &(mesh->mNormals[normal_index]);
long start = new_model->normals_num*3;
new_model->normals_num++;
new_model->normals = (float *) realloc(new_model->normals, new_model->normals_num*3*sizeof(float));
if (new_model->normals == NULL) {
fprintf(stderr, "Error: failed allocating memory for normals\n");
goto error;
}
memcpy(&new_model->normals[start], normal, sizeof(float)*3);
}
}
return new_model;
error:
aiReleaseImport(scene);
free(new_model->vertices);
free(new_model->indices);
free(new_model->normals);
free(new_model);
return NULL;
}
int record_path(struct object *obj) {
if (obj->paths_num <= obj->paths_max) {
obj->paths = (float *) reallocarray(obj->paths, (obj->paths_num+1)*3, sizeof(float));
}
if (obj->paths == NULL) {
fprintf(stderr, "Error: failed allocating memory for paths of object\n");
return -1;
}
memcpy(obj->paths+(obj->paths_num*3), obj->position, 3*sizeof(float));
if (obj->paths_num < obj->paths_max) {
obj->paths_num++;
goto end;
}
// pop first element
memmove(obj->paths, &obj->paths[3], (obj->paths_num)*3*sizeof(float));
end:
return 0;
}
struct object *create_object(struct object **o, float mass, struct model *model) {
struct object *no = malloc(sizeof(struct object));
if (no == NULL) {
return NULL;
}
memset(no, 0, sizeof(struct object));
no->mass = mass;
no->scale = 1.0f;
no->paths_max = MAX_PATHS;
no->model = model;
glm_vec4_one(no->position);
glm_vec3_one(no->color);
for (int i = 0; i < 3; i++) {
no->color[i] = 0.5f + (fabs(frand48()) / 2);
}
if (*o == NULL) {
*o = no;
return no;
}
struct object *previous_object = *o;
no->next = previous_object;
*o = no;
return no;
}

473
rendlib.c
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@ -1,473 +0,0 @@
#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <cglm/cglm.h>
#include "include/rendlib.h"
#include "include/math.h"
#include "include/object.h"
// global variables
int window_width = 960;
int window_height = 540;
char *window_title = "rendlib window";
// global settings
float fov = 80.0f; // default fov
float fov_change = 1.0f;
vec3 camera_pos = { 0.0f, 0.0f, 20.0f };
vec3 camera_front = { 0.0f, 0.0f, -1.0f };
vec3 camera_up = { 0.0f, 1.0f, 0.0f };
struct object *camera_lock = NULL; // is camera locked to any object?
float camera_yaw = -90.0f; // x rotation
float camera_pitch = 0.0f; // y rotation
float camera_sensitivity = 0.01f;
float top_movement_speed = 0.2f;
vec3 speed = { 0.0f, 0.0f, 0.0f };
GLint screen_viewport[4]; // viewport: x,y,width,height
int toggle_tracing = 0; // true or false
long added_particles = 0;
// tmp input
int inputs[8] = {0,0,0,0,0,0,};
// tmp
struct model *sphere_model;
struct object *objects;
// opengl
unsigned int shader_program;
unsigned int vertex_shader;
unsigned int fragment_shader;
// shaders
const char *object_vertex_shader_location = "assets/shaders/shader.vert";
const char *object_fragment_shader_location = "assets/shaders/shader.frag";
int load_shader(const char *path, unsigned int shader) {
FILE *fp = fopen(path, "r");
if (fp == NULL) {
fprintf(stderr, "error: cannot open file '%s'\n", path);
return -1;
}
fseek(fp, 0L, SEEK_END);
int len = ftell(fp);
if (len == -1) {
fprintf(stderr, "error: cannot fetch length of file '%s'\n", path);
return -1;
}
fseek(fp, 0L, SEEK_SET);
char *fc = (char *) malloc(len);
if (fc == NULL) {
fprintf(stderr, "error: not enough dynamic memory\n");
return -1;
}
memset(fc, 0, len);
int rb = 0;
do {
rb += fread(fc+rb, sizeof(char), len-rb, fp);
if (rb == 0) {
break;
}
} while (rb < len);
fclose(fp);
glShaderSource(shader, 1, (const char **) &fc, &rb);
glCompileShader(shader);
int success;
glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
if (success != GL_TRUE) {
int log_length;
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &log_length);
char log[log_length];
glGetShaderInfoLog(shader, log_length, NULL, log);
fprintf(stderr, "Shader Compilation Error: %s\n", log);
return -1;
}
free(fc);
return 0;
}
int load_shaders(void) {
glDeleteProgram(shader_program);
shader_program = glCreateProgram();
// create and load new shaders
vertex_shader = glCreateShader(GL_VERTEX_SHADER);
fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
if (load_shader(object_vertex_shader_location, vertex_shader) == -1) {
return -1;
}
if (load_shader(object_fragment_shader_location, fragment_shader) == -1) {
return -1;
}
// compile object shader program
glAttachShader(shader_program, vertex_shader);
glAttachShader(shader_program, fragment_shader);
glLinkProgram(shader_program);
int success;
glGetProgramiv(shader_program, GL_LINK_STATUS, &success);
if (success != GL_TRUE) {
int log_length;
glGetProgramiv(shader_program, GL_INFO_LOG_LENGTH, &log_length);
char log[log_length];
glGetProgramInfoLog(shader_program, log_length, NULL, log);
fprintf(stderr, "[object program] Shader Compilation Error: %s\n", log);
return -1;
}
glDeleteShader(vertex_shader);
glDeleteShader(fragment_shader);
return 0;
}
void handle_input(void) {
int ret = 0;
if (inputs[0]) {
exit(EXIT_SUCCESS);
inputs[0] = 0;
}
if (inputs[1]) {
ret = load_shaders();
if (ret < 0) {
fprintf(stderr, "--error: reloading shaders\n");
exit(EXIT_FAILURE);
}
inputs[1] = 0;
}
if (inputs[2]) {
vec3 side_scalar = {top_movement_speed, top_movement_speed, top_movement_speed };
vec3 camera_side;
glm_cross(camera_front, camera_up, camera_side);
glm_normalize(camera_side);
glm_vec3_mul(camera_side, side_scalar, camera_side);
glm_vec3_sub(camera_pos, camera_side, camera_pos);
}
if (inputs[3]) {
vec3 side_scalar = {top_movement_speed, top_movement_speed, top_movement_speed };
vec3 camera_side;
glm_cross(camera_front, camera_up, camera_side);
glm_normalize(camera_side);
glm_vec3_mul(camera_side, side_scalar, camera_side);
glm_vec3_add(camera_pos, camera_side, camera_pos);
}
if (inputs[4]) {
vec3 front_scalar = {top_movement_speed, top_movement_speed, top_movement_speed };
glm_vec3_mul(front_scalar, camera_front, front_scalar);
glm_vec3_sub(camera_pos, front_scalar, camera_pos);
}
if (inputs[5]) {
vec3 front_scalar = {top_movement_speed, top_movement_speed, top_movement_speed };
glm_vec3_mul(front_scalar, camera_front, front_scalar);
glm_vec3_add(camera_pos, front_scalar, camera_pos);
}
}
void window_size(GLFWwindow *w, int width, int height) {
glViewport(0, 0, width, height);
}
void display(void) {
handle_input();
GLFWwindow *w = glfwGetCurrentContext();
mat4 view;
mat4 projection;
GLint translation_uniform;
GLint view_uniform;
GLint projection_uniform;
GLint color_uniform;
GLint scale_uniform;
glClearColor(0.13f, 0.13f, 0.13f, 0.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glGetIntegerv(GL_VIEWPORT, screen_viewport);
glUseProgram(shader_program);
glm_mat4_identity(view);
vec3 camera_center;
glm_vec3_add(camera_pos, camera_front, camera_center);
glm_lookat(camera_pos, camera_center, camera_up, view);
glm_mat4_identity(projection);
glm_perspective(glm_rad(fov), (float) screen_viewport[2]/(float) screen_viewport[3], 0.01f, 100000.0f, projection);
view_uniform = glGetUniformLocation(shader_program, "view");
projection_uniform = glGetUniformLocation(shader_program, "projection");
translation_uniform = glGetUniformLocation(shader_program, "translation");
color_uniform = glGetUniformLocation(shader_program, "color");
scale_uniform = glGetUniformLocation(shader_program, "scale");
glUniformMatrix4fv(view_uniform, 1, GL_FALSE, (float *) view);
glUniformMatrix4fv(projection_uniform, 1, GL_FALSE, (float *) projection);
for (struct object *obj = objects; obj != NULL; obj = obj->next) {
mat4 translation_matrix;
glm_mat4_identity(translation_matrix);
struct model *obj_model = obj->model;
// calculate gravity
for (struct object *target = objects; target != NULL; target = target->next) {
if (target == obj) {
continue;
}
vec3 force;
glm_vec3_zero(force);
calculate_gravity(obj, target, force);
vec4 force_new;
for (int i = 0; i < 3; i++) {
force_new[i] = force[i];
}
force_new[3] = 0.0f;
float n = obj->mass;
vec4 scaler = {n,n,n,1.0f};
glm_vec4_div(force_new, scaler, force_new);
glm_vec4_add(force_new, obj->translation_force, obj->translation_force);
}
glm_vec4_add(obj->position, obj->translation_force, obj->position);
// follow object if camera locked
if (camera_lock == obj) {
glm_vec3_add(camera_pos, obj->translation_force, camera_pos);
}
// record path
if (toggle_tracing == 1) {
if (record_path(obj) == -1) {
exit(EXIT_FAILURE);
}
}
glm_translate(translation_matrix, obj->position);
glUniformMatrix4fv(translation_uniform, 1, GL_FALSE, (float *) translation_matrix);
glUniform3fv(color_uniform, 1, (float *) obj->color);
glUniform1f(scale_uniform, obj->scale);
glBindVertexArray(obj->vao);
glDrawElements(GL_TRIANGLES, obj_model->indices_num, GL_UNSIGNED_INT, (void *) 0);
glBindVertexArray(obj->pvao);
glBindBuffer(GL_ARRAY_BUFFER, obj->pbo);
glBufferData(GL_ARRAY_BUFFER, obj->paths_num*3*sizeof(float),obj->paths, GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(float), (void *) 0);
glEnableVertexAttribArray(0);
glm_mat4_identity(translation_matrix);
glUniformMatrix4fv(translation_uniform, 1, GL_FALSE, (float *) translation_matrix);
glUniform1f(scale_uniform, 1.0f);
glDrawArrays(GL_LINE_STRIP, 0, obj->paths_num);
}
/*glutPostRedisplay();
glutSwapBuffers();*/
glfwSwapBuffers(w);
glfwPollEvents();
}
void rendlib_bake_graphics(void) {
// setup default mouse position
glGetIntegerv(GL_VIEWPORT, screen_viewport);
for (struct object *obj = objects; obj != NULL; obj = obj->next) {
struct model *obj_model = obj->model;
glGenVertexArrays(1, &obj->vao);
glGenVertexArrays(1, &obj->pvao);
glGenBuffers(1, &obj->vbo);
glGenBuffers(1, &obj->ebo);
glGenBuffers(1, &obj->nbo);
glGenBuffers(1, &obj->pbo);
glBindVertexArray(obj->vao);
glBindBuffer(GL_ARRAY_BUFFER,obj->vbo);
glBufferData(GL_ARRAY_BUFFER,obj_model->vertices_num*3*sizeof(float),obj_model->vertices, GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(float), (void *) 0);
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, obj->nbo);
glBufferData(GL_ARRAY_BUFFER, obj_model->normals_num*3*sizeof(float), obj_model->normals, GL_STATIC_DRAW);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 3*sizeof(float), (void *) 0);
glEnableVertexAttribArray(1);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,obj->ebo);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, obj_model->indices_num*sizeof(unsigned int), obj_model->indices, GL_STATIC_DRAW);
glBindVertexArray(0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}
glEnable(GL_DEPTH_TEST);
}
void keyboard(GLFWwindow *w, int key, int scancode, int action, int mods) {
if (action == GLFW_PRESS) {
switch (key) {
case GLFW_KEY_ESCAPE:
inputs[0] = 1;
break;
case GLFW_KEY_R:
inputs[1] = 1;
break;
case GLFW_KEY_A:
inputs[2] = 1;
break;
case GLFW_KEY_D:
inputs[3] = 1;
break;
case GLFW_KEY_S:
inputs[4] = 1;
break;
case GLFW_KEY_W:
inputs[5] = 1;
break;
}
} else if (action == GLFW_RELEASE) {
switch (key) {
case GLFW_KEY_A:
inputs[2] = 0;
break;
case GLFW_KEY_D:
inputs[3] = 0;
break;
case GLFW_KEY_S:
inputs[4] = 0;
break;
case GLFW_KEY_W:
inputs[5] = 0;
break;
}
}
}
void mouse(int button, int state, int x, int y) {
switch (button) {
case 3:
if (fov-fov_change < 0.0f) {
break;
}
fov -= fov_change;
break;
case 4:
if (fov+fov_change > 180.0f) {
break;
}
fov += fov_change;
break;
default:
break;
}
}
int warped_pointer = 0;
int first_pointer = 1;
void mouse_motion(GLFWwindow *window, double x, double y) {
if (warped_pointer == 1) {
warped_pointer = 0;
return;
}
warped_pointer = 1;
GLFWwindow *w = glfwGetCurrentContext();
glfwSetCursorPos(w, (screen_viewport[2]/2), (screen_viewport[3]/2));
if (first_pointer == 1) {
first_pointer = 0;
return;
}
float offset_x = (float) (x - (screen_viewport[2]/2)) * camera_sensitivity;
float offset_y = (float) (y - (screen_viewport[3]/2)) * camera_sensitivity;
camera_yaw += offset_x;
camera_pitch -= offset_y;
// limit view rotation
if (camera_pitch < -89.9f) {
camera_pitch = -89.9f;
}
if (camera_pitch > 89.9f) {
camera_pitch = 89.9f;
}
vec3 view_direction;
view_direction[0] = cos(glm_rad(camera_yaw)) * cos(glm_rad(camera_pitch));
view_direction[1] = sin(glm_rad(camera_pitch));
view_direction[2] = sin(glm_rad(camera_yaw)) * cos(glm_rad(camera_pitch));
glm_normalize_to(view_direction, camera_front);
}
int rendlib_start_window(int argc, char *argv[]) {
int ret = glfwInit();
if (!ret) {
return err_glfw_init;
}
GLFWwindow *w = glfwCreateWindow(window_width, window_height, window_title, NULL, NULL);
if (w == NULL) {
return err_glfw_win;
}
glfwMakeContextCurrent(w);
glfwSetWindowSizeCallback(w, window_size);
glfwSetCursorPosCallback(w, mouse_motion);
glfwSetKeyCallback(w, keyboard);
ret = glewInit();
if (ret != GLEW_OK) {
return err_glew_init;
}
ret = load_shaders();
if (ret < 0) {
return err_shaders_init;
}
return 0;
}
int rendlib_render(void) {
rendlib_bake_graphics();
for (;;) {
display();
}
return 0;
}

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#include "batch.h"
int start_batch(struct batch **ab) {
if (*ab != NULL) {
return -1;
}
}

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#include <string.h>
#include <cglm/cam.h>
#include <GL/glew.h>
#include "camera.h"
struct camera *create_camera(int type) {
if (type != CAMERA_PERSPECTIVE &&
type != CAMERA_ORTHOGRAPHIC) {
return NULL;
}
struct camera *c = malloc(sizeof(struct camera));
if (c == NULL) {
return NULL;
}
memset(c, 0, sizeof(struct camera));
c->type = type;
c->fov = 80.0f;
c->near_z = 0.01f;
c->far_z = 1000.0f;
c->yaw = -90.0f;
c->pitch = 0.0f;
c->sensitivity = 0.02f;
if (c->type == CAMERA_ORTHOGRAPHIC) {
c->viewport_modifier = 0.5f;
}
c->pos[0] = 0.0f;
c->pos[1] = 0.0f;
c->pos[2] = 10.0f;
c->front[0] = 0.0f;
c->front[1] = 0.0f;
c->front[2] = -1.0f;
c->up[0] = 0.0f;
c->up[1] = 1.0f;
c->up[2] = 0.0f;
return c;
}
int bake_camera(struct camera *c) {
glm_mat4_identity(c->view);
glm_vec3_add(c->pos, c->front, c->center);
glm_lookat(c->pos, c->center, c->up, c->view);
glm_mat4_identity(c->projection);
int screen_viewport[4];
glGetIntegerv(GL_VIEWPORT, screen_viewport);
if (c->type == CAMERA_PERSPECTIVE) {
glm_perspective(glm_rad(c->fov),
(float) ((float)screen_viewport[2]/(float)screen_viewport[3]),
c->near_z, c->far_z,
c->projection);
} else if (c->type == CAMERA_ORTHOGRAPHIC) {
float left = -screen_viewport[2]/2 * c->viewport_modifier;
float right = screen_viewport[2]/2 * c->viewport_modifier;
float top = screen_viewport[3]/2 * c->viewport_modifier;
float bottom = -screen_viewport[3]/2 * c->viewport_modifier;
glm_ortho(left, right, bottom, top, c->near_z, c->far_z, c->projection);
} else {
return -1;
}
return 0;
}

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#include "math.h"
#include "object.h"
#include <cglm/cglm.h>
float frand48(void) {
float number = (float) rand() / (float) (RAND_MAX + 1.0);
float side = rand() % 2;
if (side == 0) {
number = -number;
}
return number;
}

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#include "object.h"
#include "math.h"
#include <math.h>
#include <assimp/cimport.h>
#include <assimp/scene.h>
#include <assimp/postprocess.h>
static int load_vertices(struct model *m, struct aiMesh *ms) {
m->vertices_num = ms->mNumVertices;
int len = m->vertices_num * sizeof(struct aiVector3D);
m->vertices = malloc(len);
if (m->vertices == NULL) {
return -1;
}
memset(m->vertices, 0, len);
memcpy(m->vertices, ms->mVertices, len);
return 0;
}
static int load_indices(struct model *m, struct aiMesh *ms) {
for (int face_index = 0; face_index < ms->mNumFaces; face_index++) {
struct aiFace *face = &(ms->mFaces[face_index]);
long start = m->indices_num;
m->indices_num += face->mNumIndices;
m->indices = (unsigned int *) realloc(m->indices, sizeof(unsigned int)*m->indices_num);
if (m->indices == NULL) {
return -1;
}
memcpy(&m->indices[start], face->mIndices, sizeof(unsigned int)*face->mNumIndices);
}
return 0;
}
static int load_normals(struct model *m, struct aiMesh *ms) {
m->normals_num = ms->mNumVertices;
int len = m->vertices_num * sizeof(struct aiVector3D);
m->normals = malloc(len);
if (m->vertices == NULL) {
return -1;
}
memset(m->normals, 0, len);
memcpy(m->normals, ms->mNormals, len);
return 0;
}
struct model *load_model(const char *path) {
int ret = 0;
struct model *nm = malloc(sizeof(struct model));
if (nm == NULL) {
return NULL;
}
memset(nm, 0, sizeof(struct model));
const struct aiScene *scene = aiImportFile(path, aiProcess_Triangulate);
if (scene == NULL) {
free(nm);
return NULL;
}
for (int mesh_index = 0; mesh_index < scene->mNumMeshes; mesh_index++) {
struct aiMesh *mesh = scene->mMeshes[mesh_index];
ret = load_vertices(nm, mesh);
if (ret < 0) {
free(nm);
aiReleaseImport(scene);
return NULL;
}
ret = load_indices(nm, mesh);
if (ret < 0) {
free(nm->vertices);
free(nm);
aiReleaseImport(scene);
return NULL;
}
ret = load_normals(nm, mesh);
if (ret < 0) {
free(nm->vertices);
free(nm->indices);
free(nm);
aiReleaseImport(scene);
return NULL;
}
}
return nm;
}
struct object *create_object(struct object **o, struct model *model) {
struct object *no = malloc(sizeof(struct object));
if (no == NULL) {
return NULL;
}
memset(no, 0, sizeof(struct object));
no->scale = 1.0f;
no->model = model;
glm_vec4_one(no->position);
glm_vec3_one(no->color);
for (int i = 0; i < 3; i++) {
no->color[i] = 0.5f + (fabs(frand48()) / 2);
}
if (*o == NULL) {
*o = no;
return no;
}
struct object *previous_object = *o;
no->next = previous_object;
*o = no;
return no;
}

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#include <time.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <cglm/cglm.h>
#include "rendlib.h"
#include "camera.h"
#include "object.h"
#include "shaders.h"
// global variables
int window_width = 960;
int window_height = 540;
char *window_title = "rendlib window";
struct camera *ac;
struct batch *ab;
void (*keyboard_probe)(int key, int scancode, int action, int mods);
void (*mouse_probe)(double x, double y);
void (*update_probe)(void);
float top_movement_speed = 0.4f;
vec3 speed = { 0.0f, 0.0f, 0.0f };
GLint screen_viewport[4];
struct object *objects;
unsigned int shader_program;
unsigned int vertex_shader;
unsigned int fragment_shader;
extern char *default_vshader;
extern char *default_fshader;
extern int default_vshader_len;
extern int default_fshader_len;
void update_screen_viewport(int x, int y, int width, int height) {
GLFWwindow *w = glfwGetCurrentContext();
glfwSetCursorPos(w, (width/2), (height/2));
glViewport(x, y, width, height);
glGetIntegerv(GL_VIEWPORT, screen_viewport);
}
int load_shader(char **s, int *n, unsigned int shader) {
glShaderSource(shader, 1, (const char **) s, n);
glCompileShader(shader);
int success;
glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
if (success != GL_TRUE) {
int log_length;
glGetShaderiv(shader, GL_INFO_LOG_LENGTH, &log_length);
char log[log_length];
glGetShaderInfoLog(shader, log_length, NULL, log);
fprintf(stderr, "Shader Compilation Error: %s\n", log);
return -1;
}
return 0;
}
int fload_shader(char *path, unsigned int shader) {
FILE *fp = fopen(path, "r");
if (fp == NULL) {
fprintf(stderr, "error: cannot open file '%s'\n", path);
return -1;
}
fseek(fp, 0L, SEEK_END);
int len = ftell(fp);
if (len == -1) {
fprintf(stderr, "error: cannot fetch length of file '%s'\n", path);
return -1;
}
fseek(fp, 0L, SEEK_SET);
char *fc = (char *) malloc(len);
if (fc == NULL) {
fprintf(stderr, "error: not enough dynamic memory\n");
return -1;
}
memset(fc, 0, len);
int rb = 0;
do {
rb += fread(fc+rb, sizeof(char), len-rb, fp);
if (rb == 0) {
break;
}
} while (rb < len);
fclose(fp);
int ret = load_shader(&fc, &rb, shader);
free(fc);
return ret;
}
int load_default_shaders(void) {
int ret = 0;
glDeleteProgram(shader_program);
shader_program = glCreateProgram();
vertex_shader = glCreateShader(GL_VERTEX_SHADER);
fragment_shader = glCreateShader(GL_FRAGMENT_SHADER);
int vshader_len = strlen(DEFAULT_VSHADER);
char *vshader = strndup(DEFAULT_VSHADER, vshader_len);
if (vshader == NULL) {
return -1;
}
ret = load_shader(&vshader, &vshader_len, vertex_shader);
if (ret < 0) {
return -1;
}
free(vshader);
int fshader_len = strlen(DEFAULT_FSHADER);
char *fshader = strndup(DEFAULT_FSHADER, fshader_len);
if (fshader == NULL) {
return -1;
}
ret = load_shader(&fshader, &fshader_len, fragment_shader);
if (ret < 0) {
return -1;
}
free(fshader);
glAttachShader(shader_program, vertex_shader);
glAttachShader(shader_program, fragment_shader);
glLinkProgram(shader_program);
int success;
glGetProgramiv(shader_program, GL_LINK_STATUS, &success);
if (success != GL_TRUE) {
int log_length;
glGetProgramiv(shader_program, GL_INFO_LOG_LENGTH, &log_length);
char log[log_length];
glGetProgramInfoLog(shader_program, log_length, NULL, log);
fprintf(stderr, "[object program] Shader Compilation Error: %s\n", log);
return -1;
}
glDeleteShader(vertex_shader);
glDeleteShader(fragment_shader);
return 0;
}
void handle_input(void) {
}
void window_size(GLFWwindow *w, int width, int height) {
update_screen_viewport(0, 0, width, height);
}
void display(void) {
handle_input();
GLFWwindow *w = glfwGetCurrentContext();
GLint translation_uniform;
GLint view_uniform;
GLint projection_uniform;
GLint color_uniform;
GLint scale_uniform;
glClearColor(0.13f, 0.13f, 0.13f, 0.0f);
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glUseProgram(shader_program);
int ret = bake_camera(ac);
if (ret < 0) {
fprintf(stderr, "--error: failed baking camera\n");
return;
}
view_uniform = glGetUniformLocation(shader_program, "view");
projection_uniform = glGetUniformLocation(shader_program, "projection");
translation_uniform = glGetUniformLocation(shader_program, "translation");
color_uniform = glGetUniformLocation(shader_program, "color");
scale_uniform = glGetUniformLocation(shader_program, "scale");
glUniformMatrix4fv(view_uniform, 1, GL_FALSE, (float *) ac->view);
glUniformMatrix4fv(projection_uniform, 1, GL_FALSE, (float *) ac->projection);
for (struct object *obj = objects; obj != NULL; obj = obj->next) {
mat4 translation_matrix;
glm_mat4_identity(translation_matrix);
struct model *obj_model = obj->model;
glm_translate(translation_matrix, obj->position);
glUniformMatrix4fv(translation_uniform, 1, GL_FALSE, (float *) translation_matrix);
glUniform3fv(color_uniform, 1, (float *) obj->color);
glUniform1f(scale_uniform, obj->scale);
glBindVertexArray(obj->vao);
glDrawElements(GL_TRIANGLES, obj_model->indices_num, GL_UNSIGNED_INT, (void *) 0);
}
glfwSwapBuffers(w);
glfwPollEvents();
}
void rendlib_bake_graphics(void) {
glGetIntegerv(GL_VIEWPORT, screen_viewport);
for (struct object *obj = objects; obj != NULL; obj = obj->next) {
struct model *obj_model = obj->model;
glGenVertexArrays(1, &obj->vao);
glGenBuffers(1, &obj->vbo);
glGenBuffers(1, &obj->ebo);
glGenBuffers(1, &obj->nbo);
glBindVertexArray(obj->vao);
glBindBuffer(GL_ARRAY_BUFFER,obj->vbo);
glBufferData(GL_ARRAY_BUFFER,obj_model->vertices_num*3*sizeof(float),obj_model->vertices, GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3*sizeof(float), (void *) 0);
glEnableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, obj->nbo);
glBufferData(GL_ARRAY_BUFFER, obj_model->normals_num*3*sizeof(float), obj_model->normals, GL_STATIC_DRAW);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 3*sizeof(float), (void *) 0);
glEnableVertexAttribArray(1);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER,obj->ebo);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, obj_model->indices_num*sizeof(unsigned int), obj_model->indices, GL_STATIC_DRAW);
glBindVertexArray(0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}
glEnable(GL_DEPTH_TEST);
}
void keyboard(GLFWwindow *w, int key, int scancode, int action, int mods) {
if (keyboard_probe == NULL) {
return;
}
(keyboard_probe)(key, scancode, action, mods);
}
void mouse_motion(GLFWwindow *window, double x, double y) {
if (mouse_probe == NULL) {
return;
}
(mouse_probe)(x, y);
}
int rendlib_start_window(int argc, char *argv[]) {
int ret = glfwInit();
if (!ret) {
return err_glfw_init;
}
GLFWwindow *w = glfwCreateWindow(window_width, window_height, window_title, NULL, NULL);
if (w == NULL) {
return err_glfw_win;
}
glfwMakeContextCurrent(w);
glfwSetWindowSizeCallback(w, window_size);
glfwSetCursorPosCallback(w, mouse_motion);
glfwSetKeyCallback(w, keyboard);
glfwSetInputMode(w, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
ret = glewInit();
if (ret != GLEW_OK) {
return err_glew_init;
}
ret = load_default_shaders();
if (ret < 0) {
return err_shaders_init;
}
return 0;
}
int setup_default_camera(void) {
ac = create_camera(CAMERA_PERSPECTIVE);
if (ac == NULL) {
return -1;
}
return 0;
}
int rendlib_render(void) {
if (ac == NULL) {
if (setup_default_camera() < 0) {
return -1;
}
}
rendlib_bake_graphics();
for (;;) {
if (update_probe != NULL) {
(update_probe)();
}
display();
}
return 0;
}

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#include <stdlib.h>
#include <stdio.h>
#include <GLFW/glfw3.h>
#include "rendlib.h"
#include "camera.h"
#include "object.h"
#define INPUT_ESCAPE 0b00000001
#define INPUT_RELOAD 0b00000010
#define INPUT_LEFT 0b00000100
#define INPUT_RIGHT 0b00001000
#define INPUT_DOWN 0b00010000
#define INPUT_UP 0b00100000
#define MOVEMENT_SPEED 0.2f
char input = 0;
void keyboardp(int key, int scancode, int action, int mods) {
if (action == GLFW_PRESS) {
switch (key) {
case GLFW_KEY_Q:
case GLFW_KEY_ESCAPE:
input |= INPUT_ESCAPE;
break;
case GLFW_KEY_R:
input |= INPUT_RELOAD;
break;
case GLFW_KEY_A:
case GLFW_KEY_LEFT:
input |= INPUT_LEFT;
break;
case GLFW_KEY_D:
case GLFW_KEY_RIGHT:
input |= INPUT_RIGHT;
break;
case GLFW_KEY_S:
case GLFW_KEY_DOWN:
input |= INPUT_DOWN;
break;
case GLFW_KEY_W:
case GLFW_KEY_UP:
input |= INPUT_UP;
break;
}
} else if (action == GLFW_RELEASE) {
switch (key) {
case GLFW_KEY_A:
case GLFW_KEY_LEFT:
input &= ~INPUT_LEFT;
break;
case GLFW_KEY_D:
case GLFW_KEY_RIGHT:
input &= ~INPUT_RIGHT;
break;
case GLFW_KEY_S:
case GLFW_KEY_DOWN:
input &= ~INPUT_DOWN;
break;
case GLFW_KEY_W:
case GLFW_KEY_UP:
input &= ~INPUT_UP;
break;
}
}
}
int warped_pointer = 0;
int first_pointer = 1;
void mousep(double x, double y) {
GLint screen_viewport[4];
if (warped_pointer == 1) {
warped_pointer = 0;
return;
}
warped_pointer = 1;
glGetIntegerv(GL_VIEWPORT, screen_viewport);
GLFWwindow *w = glfwGetCurrentContext();
glfwSetCursorPos(w, (screen_viewport[2]/2), (screen_viewport[3]/2));
if (first_pointer == 1) {
first_pointer = 0;
return;
}
float offset_x = (float) (x - (screen_viewport[2]/2)) * ac->sensitivity;
float offset_y = (float) (y - (screen_viewport[3]/2)) * ac->sensitivity;
ac->yaw += offset_x;
ac->pitch -= offset_y;
if (ac->pitch < -89.9f) {
ac->pitch = -89.9f;
}
if (ac->pitch > 89.9f) {
ac->pitch = 89.9f;
}
vec3 view_direction = { cos(glm_rad(ac->yaw)) * cos(glm_rad(ac->pitch)),
sin(glm_rad(ac->pitch)),
sin(glm_rad(ac->yaw)) * cos(glm_rad(ac->pitch))
};
glm_normalize_to(view_direction, ac->front);
}
void periodic_input(void) {
int ret = 0;
if (input & INPUT_ESCAPE) {
exit(EXIT_SUCCESS);
input &= ~INPUT_ESCAPE;
}
if (input & INPUT_LEFT) {
vec3 side_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED, MOVEMENT_SPEED};
vec3 camera_side;
glm_cross(ac->front, ac->up, camera_side);
glm_normalize(camera_side);
glm_vec3_mul(camera_side, side_scalar, camera_side);
glm_vec3_sub(ac->pos, camera_side, ac->pos);
}
if (input & INPUT_RIGHT) {
vec3 side_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED, MOVEMENT_SPEED};
vec3 camera_side;
glm_cross(ac->front, ac->up, camera_side);
glm_normalize(camera_side);
glm_vec3_mul(camera_side, side_scalar, camera_side);
glm_vec3_add(ac->pos, camera_side, ac->pos);
}
if (input & INPUT_DOWN) {
vec3 front_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED, MOVEMENT_SPEED};
glm_vec3_mul(front_scalar, ac->front, front_scalar);
glm_vec3_sub(ac->pos, front_scalar, ac->pos);
}
if (input & INPUT_UP) {
vec3 front_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED, MOVEMENT_SPEED};
glm_vec3_mul(front_scalar, ac->front, front_scalar);
glm_vec3_add(ac->pos, front_scalar, ac->pos);
}
}
void updatep(void) {
periodic_input();
}
int main(int argc, char *argv[]) {
int ret = rendlib_start_window(argc, argv);
if (ret < 0) {
fprintf(stderr, "--error: %d\n", ret);
return EXIT_FAILURE;
}
keyboard_probe = &keyboardp;
mouse_probe = &mousep;
update_probe = &updatep;
struct model *m = load_model("assets-01/sphere.obj");
if (m == NULL) {
fprintf(stderr, "--error: loading model\n");
return EXIT_FAILURE;
}
struct object *o = create_object(&objects, m);
if (o == NULL) {
fprintf(stderr, "--error: creating object\n");
return EXIT_FAILURE;
}
ac = create_camera(CAMERA_PERSPECTIVE);
if (ac == NULL) {
fprintf(stderr, "--error: creating camera\n");
return EXIT_FAILURE;
}
ret = rendlib_render();
if (ret < 0) {
fprintf(stderr, "--error: %d\n", ret);
return EXIT_FAILURE;
}
fprintf(stdout, "--rendering\n");
return EXIT_SUCCESS;
}