7 files changed, 507 insertions, 0 deletions
diff --git a/mons_3d/src/color.c b/mons_3d/src/color.c
new file mode 100644
index 0000000..1b1627d
--- /dev/null
+++ b/mons_3d/src/color.c
@@ -0,0 +1 @@
+#include "color.h"
diff --git a/mons_3d/src/mesh.c b/mons_3d/src/mesh.c
new file mode 100644
index 0000000..213a24c
--- /dev/null
+++ b/mons_3d/src/mesh.c
@@ -0,0 +1,124 @@
+#include "mesh.h"
+#include "vertex.h"
+#include "mikktspace.h"
+
+#include <glad/gl.h>
+#include <stdlib.h>
+
+void compute_tangents(mons_vertex *vertex_array, int vertex_count, int *index_array, int index_count);
+
+mons_mesh mons_create_mesh(mons_vertex *vertex_array, int vertex_count, int *index_array, int index_count) {
+    compute_tangents(vertex_array, vertex_count, index_array, index_count);
+    // VAO & VBO
+    unsigned int vao;
+    glGenVertexArrays(1, &vao);
+    glBindVertexArray(vao);
+    unsigned int vbo;
+    glGenBuffers(1, &vbo);
+    glBindBuffer(GL_ARRAY_BUFFER, vbo);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(mons_vertex) * vertex_count, vertex_array, GL_STATIC_DRAW);
+    unsigned int ebo;
+    glGenBuffers(1, &ebo);
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, ebo);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(unsigned int) * index_count, index_array, GL_STATIC_DRAW);
+    // Set up vertex attributes
+    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, sizeof(mons_vertex), 0);
+    glEnableVertexAttribArray(0);
+    glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, sizeof(mons_vertex), (void*)(sizeof(mons_vec3)));
+    glEnableVertexAttribArray(1);
+    glVertexAttribPointer(2, 4, GL_FLOAT, GL_FALSE, sizeof(mons_vertex), (void*)(sizeof(mons_vec3) * 2));
+    glEnableVertexAttribArray(2);
+    glVertexAttribPointer(3, 2, GL_FLOAT, GL_FALSE, sizeof(mons_vertex), (void*)(sizeof(mons_vec3) * 2 + sizeof(mons_vec4)));
+    glEnableVertexAttribArray(3);
+    return (mons_mesh) {
+        .vao = vao,
+        .element_count = index_count,
+    };
+}
+
+struct mesh_data {
+    mons_vertex *vertex_array;
+    int vertex_count;
+    int *index_array;
+    int index_count;
+};
+
+int get_vertex_index(const SMikkTSpaceContext *context, int i_face, int i_vert) {
+    struct mesh_data *mesh_data = context->m_pUserData;
+    int index_index = (i_face * 3) + i_vert;
+    int index = mesh_data->index_array[index_index];
+    return index;
+}
+
+int get_num_faces(const SMikkTSpaceContext *context) {
+    struct mesh_data *mesh_data = context->m_pUserData;
+    return mesh_data->index_count / 3;
+}
+
+int get_num_vertices_of_face(const SMikkTSpaceContext *context, int i_face) {
+    return 3;
+}
+
+void get_position(const SMikkTSpaceContext *context, float *outpos, int i_face, int i_vert) {
+    struct mesh_data *mesh_data = context->m_pUserData;
+    int index = get_vertex_index(context, i_face, i_vert);
+    mons_vertex vertex = mesh_data->vertex_array[index];
+
+    outpos[0] = vertex.position.x;
+    outpos[1] = vertex.position.y;
+    outpos[2] = vertex.position.z;
+}
+
+void get_normal(const SMikkTSpaceContext *context, float *outnormal, int i_face, int i_vert) {
+    struct mesh_data *mesh_data = context->m_pUserData;
+    int index = get_vertex_index(context, i_face, i_vert);
+    mons_vertex vertex = mesh_data->vertex_array[index];
+
+    outnormal[0] = vertex.normal.x;
+    outnormal[1] = vertex.normal.y;
+    outnormal[2] = vertex.normal.z;
+}
+
+void get_tex_coords(const SMikkTSpaceContext *context, float *outuv, int i_face, int i_vert) {
+    struct mesh_data *mesh_data = context->m_pUserData;
+    int index = get_vertex_index(context, i_face, i_vert);
+    mons_vertex vertex = mesh_data->vertex_array[index];
+
+    outuv[0] = vertex.texture_coords.x;
+    outuv[1] = vertex.texture_coords.y;
+}
+
+void set_tspace_basic(const SMikkTSpaceContext *context, const float *tangentu, float f_sign, int i_face, int i_vert) {
+    struct mesh_data *mesh_data = context->m_pUserData;
+    int index = get_vertex_index(context, i_face, i_vert);
+    mons_vertex *vertex = &mesh_data->vertex_array[index];
+
+    vertex->tangent.x = tangentu[0];
+    vertex->tangent.y = tangentu[1];
+    vertex->tangent.z = tangentu[2];
+    vertex->tangent.w = f_sign;
+}
+
+void compute_tangents(mons_vertex *vertex_array, int vertex_count, int *index_array, int index_count) {
+    static SMikkTSpaceInterface iface = {
+        .m_getNumFaces = get_num_faces,
+        .m_getNumVerticesOfFace = get_num_vertices_of_face,
+        .m_getNormal = get_normal,
+        .m_getPosition = get_position,
+        .m_getTexCoord = get_tex_coords,
+        .m_setTSpaceBasic = set_tspace_basic,
+    };
+    struct mesh_data mesh_data = {
+        vertex_array,
+        vertex_count,
+        index_array,
+        index_count,
+    };
+    SMikkTSpaceContext context = {
+        .m_pInterface = &iface,
+        .m_pUserData = &mesh_data,
+    };
+
+    genTangSpaceDefault(&context);
+}
+
diff --git a/mons_3d/src/model.c b/mons_3d/src/model.c
new file mode 100644
index 0000000..ed2e543
--- /dev/null
+++ b/mons_3d/src/model.c
@@ -0,0 +1,15 @@
+#include "model.h"
+#include "texture.h"
+#include "camera.h"
+#include <glad/gl.h>
+
+void mons_model_draw(mons_model model) {
+    glUseProgram(model.shader);
+    mons_shader_apply_global_uniforms(model.shader);
+    mons_shader_set_mat4(model.shader, "transform", mons_transform_matrix(model.transform), GL_TRUE);
+    for (int i = 0; i < model.textures_len; i++) {
+        mons_texture_bind(model.shader, i, model.textures[i]);
+    }
+    glBindVertexArray(model.mesh.vao);
+    glDrawElements(GL_TRIANGLES, model.mesh.element_count, GL_UNSIGNED_INT, 0);
+}
diff --git a/mons_3d/src/projection.c b/mons_3d/src/projection.c
new file mode 100644
index 0000000..287d59e
--- /dev/null
+++ b/mons_3d/src/projection.c
@@ -0,0 +1,15 @@
+#include "projection.h"
+#include <math.h>
+#include "mons_math/mat4.h"
+
+mons_mat4 mons_projection_matrix(mons_projection projection) {
+    float tangent = tanf(projection.fov / 2.0f);
+    float top = projection.near * tangent;
+    float right = top * projection.aspect_ratio;
+    return (mons_mat4){
+        {projection.near / right, 0, 0, 0},
+        {0, projection.near / top, 0, 0},
+        {0, 0, -(projection.far + projection.near) / (projection.far - projection.near), -1},
+        {0, 0, -(2.0f * projection.far * projection.near) / (projection.far - projection.near), 0},
+    };
+}
diff --git a/mons_3d/src/shader.c b/mons_3d/src/shader.c
new file mode 100644
index 0000000..6898a1f
--- /dev/null
+++ b/mons_3d/src/shader.c
@@ -0,0 +1,185 @@
+#include <stdio.h>
+#include <stdbool.h>
+#include "shader.h"
+#include "mons_math/vec4.h"
+#include "mons_math/vec3.h"
+#include "mons_math/vec2.h"
+#include "mons_math/mat4.h"
+#include "hashmap.h"
+#include <stdlib.h>
+
+typedef enum mons_uniform_type {
+    MONS_UNIFORM_INT,
+    MONS_UNIFORM_FLOAT,
+    MONS_UNIFORM_VEC2,
+    MONS_UNIFORM_VEC3,
+    MONS_UNIFORM_VEC4,
+    MONS_UNIFORM_MAT4,
+} mons_uniform_type;
+
+typedef struct mons_uniform_m4 {
+    mons_mat4 matrix;
+    bool transpose;
+} mons_uniform_m4;
+
+typedef union mons_uniform_data {
+    int i;
+    float f;
+    mons_vec2 v2;
+    mons_vec3 v3;
+    mons_vec4 v4;
+    mons_uniform_m4 m4;
+} mons_uniform_data;
+
+typedef struct mons_uniform {
+    mons_uniform_type type;
+    mons_uniform_data data;
+} mons_uniform;
+
+static mons_hashmap *GLOBAL_UNIFORMS = NULL;
+mons_hashmap *get_global_uniforms() {
+    if (GLOBAL_UNIFORMS == NULL) {
+        GLOBAL_UNIFORMS = malloc(sizeof(mons_hashmap));
+        *GLOBAL_UNIFORMS = mons_hashmap_new(sizeof(mons_uniform), 10);
+    }
+    return GLOBAL_UNIFORMS;
+}
+
+void mons_shader_apply_global_uniforms(mons_program shader) {
+    mons_hashmap *global_uniforms = get_global_uniforms();
+    for (int i = 0; i < global_uniforms->len; i++) {
+        mons_hashmap_pair pair;
+        mons_hashmap_at(*global_uniforms, i, &pair);
+        char *name = pair.key;
+        mons_uniform uniform = *(mons_uniform *)pair.value;
+        switch (uniform.type) {
+        case MONS_UNIFORM_INT:
+            // TODO:
+            break;
+        case MONS_UNIFORM_FLOAT:
+            mons_shader_set_float(shader, name, uniform.data.f);
+            break;
+        case MONS_UNIFORM_VEC2:
+            mons_shader_set_vec2(shader, name, uniform.data.v2);
+            break;
+        case MONS_UNIFORM_VEC3:
+            mons_shader_set_vec3(shader, name, uniform.data.v3);
+            break;
+        case MONS_UNIFORM_VEC4:
+            mons_shader_set_vec4(shader, name, uniform.data.v4);
+            break;
+        case MONS_UNIFORM_MAT4:
+            mons_shader_set_mat4(shader, name, uniform.data.m4.matrix, uniform.data.m4.transpose);
+            break;
+        }
+    }
+}
+
+void mons_shader_set_float_global(char *uniform_name, float value) {
+    mons_hashmap *global_uniforms = get_global_uniforms();
+    mons_uniform uniform = {
+        .type = MONS_UNIFORM_FLOAT,
+        .data.f = value,
+    };
+    mons_hashmap_insert(global_uniforms, uniform_name, &uniform);
+}
+
+void mons_shader_set_vec2_global(char *uniform_name, mons_vec2 value) {
+    mons_hashmap *global_uniforms = get_global_uniforms();
+    mons_uniform uniform = {
+        .type = MONS_UNIFORM_VEC2,
+        .data.v2 = value,
+    };
+    mons_hashmap_insert(global_uniforms, uniform_name, &uniform);
+}
+
+void mons_shader_set_vec3_global(char *uniform_name, mons_vec3 value) {
+    mons_hashmap *global_uniforms = get_global_uniforms();
+    mons_uniform uniform = {
+        .type = MONS_UNIFORM_VEC3,
+        .data.v3 = value,
+    };
+    mons_hashmap_insert(global_uniforms, uniform_name, &uniform);
+}
+
+void mons_shader_set_vec4_global(char *uniform_name, mons_vec4 value) {
+    mons_hashmap *global_uniforms = get_global_uniforms();
+    mons_uniform uniform = {
+        .type = MONS_UNIFORM_VEC4,
+        .data.v4 = value,
+    };
+    mons_hashmap_insert(global_uniforms, uniform_name, &uniform);
+}
+
+void mons_shader_set_mat4_global(char *uniform_name, mons_mat4 value, bool transpose) {
+    mons_hashmap *global_uniforms = get_global_uniforms();
+    mons_uniform uniform = {
+        .type = MONS_UNIFORM_MAT4,
+        .data.m4 = {
+            .matrix = value,
+            .transpose = transpose,
+        },
+    };
+    mons_hashmap_insert(global_uniforms, uniform_name, &uniform);
+}
+
+mons_shader mons_create_shader(mons_shader_type shader_type, char *source,
+                               int source_length) {
+    unsigned int shader = glCreateShader(shader_type);
+    const char *shader_source = (const char *)source;
+    int shader_len = (int)source_length;
+    glShaderSource(shader, 1, &shader_source, &shader_len);
+    glCompileShader(shader);
+    int success;
+    char info_log[512];
+    glGetShaderiv(shader, GL_COMPILE_STATUS, &success);
+    if (!success) {
+        glGetShaderInfoLog(shader, 512, NULL, info_log);
+        printf("Shader Compilation Failed: %s\n", info_log);
+    }
+    return shader;
+}
+
+mons_program mons_create_program(mons_shader vertex_shader,
+                                 mons_shader fragment_shader) {
+    unsigned int shader_program = glCreateProgram();
+    glAttachShader(shader_program, vertex_shader);
+    glAttachShader(shader_program, fragment_shader);
+    glLinkProgram(shader_program);
+    int success;
+    char info_log[512];
+    glGetProgramiv(shader_program, GL_LINK_STATUS, &success);
+    if (!success) {
+        glGetProgramInfoLog(shader_program, 512, NULL, info_log);
+    }
+    return shader_program;
+}
+
+void mons_shader_set_float(mons_program shader, char *uniform_name,
+                           float value) {
+    glUniform1f(glGetUniformLocation(shader, uniform_name), value);
+}
+
+void mons_shader_set_vec2(mons_program shader, char *uniform_name,
+                          mons_vec2 value) {
+    glUniform2fv(glGetUniformLocation(shader, uniform_name), 1,
+                 (float *)&value);
+}
+
+void mons_shader_set_vec3(mons_program shader, char *uniform_name,
+                          mons_vec3 value) {
+    glUniform3fv(glGetUniformLocation(shader, uniform_name), 1,
+                 (float *)&value);
+}
+
+void mons_shader_set_vec4(mons_program shader, char *uniform_name,
+                          mons_vec4 value) {
+    glUniform4fv(glGetUniformLocation(shader, uniform_name), 1,
+                 (float *)&value);
+}
+
+void mons_shader_set_mat4(mons_program shader, char *uniform_name,
+                          mons_mat4 value, bool transpose) {
+    glUniformMatrix4fv(glGetUniformLocation(shader, uniform_name), 1, transpose,
+                       (float *)&value);
+}
diff --git a/mons_3d/src/texture.c b/mons_3d/src/texture.c
new file mode 100644
index 0000000..7b2a478
--- /dev/null
+++ b/mons_3d/src/texture.c
@@ -0,0 +1,55 @@
+#include "texture.h"
+#include "qoi.h"
+
+#include <glad/gl.h>
+
+mons_texture mons_texture_load(FILE *stream) {
+    mons_image image = mons_load_qoi(stream);
+    return mons_texture_from_image(image);
+}
+
+mons_texture mons_texture_from_image(mons_image image) {
+    glTextureParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+    glTextureParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+    glTextureParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER,
+                        GL_NEAREST_MIPMAP_LINEAR);
+    glTextureParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    unsigned int texture;
+    glGenTextures(1, &texture);
+    glBindTexture(GL_TEXTURE_2D, texture);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, image.width, image.height, 0,
+                 GL_RGBA, GL_UNSIGNED_BYTE, image.data);
+    glGenerateMipmap(GL_TEXTURE_2D);
+    mons_texture result = {
+        .id = texture,
+        .width = image.width,
+        .height = image.height,
+    };
+    mons_image_free(&image);
+    return result;
+}
+
+char *texure_uniforms[16] = {
+    "base_texture",
+    "normal_texture",
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+};
+
+void mons_texture_bind(mons_program shader, unsigned int unit, mons_texture texture) {
+    glActiveTexture(GL_TEXTURE0 + unit);
+    glUniform1i(glGetUniformLocation(shader, texure_uniforms[unit]), unit);
+    glBindTexture(GL_TEXTURE_2D, texture.id);
+}
diff --git a/mons_3d/src/transform.c b/mons_3d/src/transform.c
new file mode 100644
index 0000000..c4435fc
--- /dev/null
+++ b/mons_3d/src/transform.c
@@ -0,0 +1,112 @@
+#include <math.h>
+#include "transform.h"
+#include "mons_math/vec3.h"
+#include "mons_math/quat.h"
+#include <stdio.h>
+
+mons_mat4 translation_to_mat4(mons_vec3 translation) {
+    mons_mat4 result = MONS_MAT4_IDENTITY;
+    result.m1.w = translation.x;
+    result.m2.w = translation.y;
+    result.m3.w = translation.z;
+    return result;
+}
+
+mons_mat4 scale_to_mat4(mons_vec3 scale) {
+    mons_mat4 result = MONS_MAT4_IDENTITY;
+    result.m1.x = scale.x;
+    result.m2.y = scale.y;
+    result.m3.z = scale.z;
+    return result;
+}
+
+void mons_transform_translate(mons_transform *transform,
+                              mons_vec3 translation) {
+    mons_vec3_add_inplace(&transform->translation, translation);
+}
+
+void mons_transform_rotate(mons_transform *transform, mons_quat rotation) {
+    mons_quat_mul_inplace(&transform->rotation, rotation);
+}
+
+void mons_transform_scale(mons_transform *transform, mons_vec3 scale) {
+    mons_vec3_mul_memberwise_inplace(&transform->scale, scale);
+}
+
+mons_mat4 mons_transform_matrix(mons_transform transform) {
+    mons_mat4 translation = translation_to_mat4(transform.translation);
+    mons_mat4 result = translation;
+    mons_mat4_mul_inplace(&result, mons_quat_to_mat4(transform.rotation));
+    mons_mat4_mul_inplace(&result, scale_to_mat4(transform.scale));
+    return result;
+}
+
+mons_vec3 mons_transform_forward(mons_transform transform) {
+    return mons_quat_transform_vec3(transform.rotation, MONS_VEC3_Z);
+}
+
+mons_vec3 mons_transform_up(mons_transform transform) {
+    return mons_quat_transform_vec3(transform.rotation, MONS_VEC3_Y);
+}
+
+mons_vec3 mons_transform_right(mons_transform transform) {
+    return mons_quat_transform_vec3(transform.rotation, MONS_VEC3_X);
+}
+
+void mons_transform_look_at(mons_transform *transform, mons_vec3 point, mons_vec3 up) {
+    mons_vec3 forward = mons_vec3_normalize(mons_vec3_sub(transform->translation, point));
+    mons_vec3 right = mons_vec3_normalize(mons_vec3_cross(up, forward));
+    mons_vec3 new_up = mons_vec3_cross(forward, right);
+    float m00 = right.x;
+    float m01 = right.y;
+    float m02 = right.z;
+    float m10 = new_up.x;
+    float m11 = new_up.y;
+    float m12 = new_up.z;
+    float m20 = forward.x;
+    float m21 = forward.y;
+    float m22 = forward.z;
+
+    float num8 = (m00 + m11) + m22;
+    mons_quat quaternion = {0};
+    if (num8 > 0.0f) {
+        float num = sqrt(num8 + 1.0f);
+        quaternion.w = num * 0.5f;
+        num = 0.5f / num;
+        quaternion.x = (m12 - m21) * num;
+        quaternion.y = (m20 - m02) * num;
+        quaternion.z = (m01 - m10) * num;
+        transform->rotation = quaternion;
+        return;
+    }
+    if ((m00 >= m11) && (m00 >= m22))
+    {
+        float num7 = (float)sqrt(((1.0f + m00) - m11) - m22);
+        float num4 = 0.5f / num7;
+        quaternion.x = 0.5f * num7;
+        quaternion.y = (m01 + m10) * num4;
+        quaternion.z = (m02 + m20) * num4;
+        quaternion.w = (m12 - m21) * num4;
+        transform->rotation = quaternion;
+        return;
+    }
+    if (m11 > m22)
+    {
+        float num6 = (float)sqrt(((1.0f + m11) - m00) - m22);
+        float num3 = 0.5f / num6;
+        quaternion.x = (m10 + m01) * num3;
+        quaternion.y = 0.5f * num6;
+        quaternion.z = (m21 + m12) * num3;
+        quaternion.w = (m20 - m02) * num3;
+        transform->rotation = quaternion;
+        return;
+    }
+    float num5 = (float)sqrt(((1.0f + m22) - m00) - m11);
+    float num2 = 0.5f / num5;
+    quaternion.x = (m20 + m02) * num2;
+    quaternion.y = (m21 + m12) * num2;
+    quaternion.z = 0.5f * num5;
+    quaternion.w = (m01 - m10) * num2;
+    transform->rotation = quaternion;
+    return;
+}