Phireh/hexnando
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Add ortographic camera

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Phireh 2023-04-30 17:18:15 +02:00
commit 8c4b7bff18
5 changed files with 202 additions and 14 deletions
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4
Makefile
View file

@ -1,5 +1,5 @@
CFLAGS=-Wall -Wextra -g -pedantic -fenable-matrix -Wno-gnu-zero-variadic-macro-arguments -Wno-incompatible-pointer-types-discards-qualifiers
CFLAGS=-Wall -Wextra -g3 -pedantic -fenable-matrix -Wno-gnu-zero-variadic-macro-arguments -Wno-incompatible-pointer-types-discards-qualifiers -fsanitize=undefined -fsanitize-trap -Wconversion -Wno-implicit-int-float-conversion -Wno-implicit-float-conversion -Wno-gnu-empty-initializer
LIBS=`pkg-config --libs glfw3 glew opengl` -lm
hexnando: main.c Makefile
hexnando: main.c Makefile hex_math.h hex_debug.h
clang ${CFLAGS} ${LIBS} main.c -o hexnando

12
hex_debug.h Normal file
View file

@ -0,0 +1,12 @@
#ifndef HEX_DEBUG_H
#include <stdio.h>
#define DEBUG_VERBOSITY 1
#define log_err(str, ...) do { fprintf(stderr, "[ERROR] (%s:%d): " str "\n", __FILE__, __LINE__, ##__VA_ARGS__); } while (0)
#if (DEBUG_VERBOSITY > 0)
#define log_debug(str, ...) do { fprintf(stderr, "[DEBUG] (%s:%d): " str "\n", __FILE__, __LINE__, ##__VA_ARGS__); } while (0)
#else
#define log_debug(str, ...)
#endif
#endif

87
hex_math.h
View file

@ -1,10 +1,26 @@
#define _USE_MATH_DEFINES // for finding things like M_PI in Windows build
#include <math.h>
#include <stdint.h>
#include "hex_debug.h"
/* Types */
typedef float _v2f __attribute__((matrix_type(1,2)));
typedef float _v3f __attribute__((matrix_type(1,3)));
typedef float _v4f __attribute__((matrix_type(1,4)));
typedef float _mat4 __attribute__((matrix_type(4,4)));
typedef struct {
union {
struct {
float first;
float second;
};
_v2f v2f;
struct {
float x;
float y;
};
};
} vec2f;
typedef struct {
union {
@ -36,6 +52,37 @@ typedef struct {
};
} vec4f;
/* Row-major matrix, make sure to pass it to OpenGL trasposed */
typedef struct {
union {
_mat4 m4f;
struct {
float a0;
float a1;
float a2;
float a3;
float b0;
float b1;
float b2;
float b3;
float c0;
float c1;
float c2;
float c3;
float d0;
float d1;
float d2;
float d3;
};
struct {
vec4f row0;
vec4f row1;
vec4f row2;
vec4f row3;
};
};
} mat4f;
typedef struct {
vec4f position; // center pos
float radius; // side length
@ -44,7 +91,6 @@ typedef struct {
uint32_t vbo;
float vertices[7*3]; // 7 vert per hex
unsigned int indices[6*3]; // 6 triangles to render a hex
} hex_t;
typedef struct {
@ -53,7 +99,17 @@ typedef struct {
uint32_t columns;
} hexgrid_t;
typedef struct {
float left;
float right;
float top;
float bottom;
float near;
float far;
} camera_t;
_Static_assert(sizeof(vec4f) == sizeof(float) * 4, "Bad vector size");
_Static_assert(sizeof(mat4f) == sizeof(float) * 16, "Bad matrix size");
/* Functions */
double sint(double turns)
@ -65,3 +121,32 @@ double cost(double turns)
{
return cos(turns*2*M_PI);
}
mat4f ortho_matrix(float left, float right, float top, float bottom, float near, float far, float width, float height)
{
// Invert Y coord
float aux;
aux = bottom;
bottom = top;
top = aux;
// Scale and move to [-1,1]
left = (left*2 - width)/width;
right = (right*2 - width)/width;
top = (top*2 - height)/height;
bottom = (bottom*2 - height)/height;
mat4f matrix = {};
matrix.a0 = 2/(right - left);
matrix.a3 = -((right + left)/(right - left));
matrix.b1 = 2/(top - bottom);
matrix.b3 = -((top + bottom)/(top - bottom));
matrix.c2 = -2/(far - near);
matrix.c3 = -((far + near)/(far - near));
matrix.d3 = 1;
return matrix;
}

105
main.c
View file

@ -8,9 +8,8 @@
#include <stdlib.h>
#include "hex_math.h"
#include "hex_debug.h"
#define log_err(str, ...) do { fprintf(stderr, "[ERROR] (%s:%d): " str "\n", __FILE__, __LINE__, ##__VA_ARGS__); } while (0)
#define log_debug(str, ...) do { fprintf(stderr, "[DEBUG] (%s:%d): " str "\n", __FILE__, __LINE__, ##__VA_ARGS__); } while (0)
char *read_entire_file(char *path)
{
@ -20,7 +19,7 @@ char *read_entire_file(char *path)
if (f)
{
fseek(f, 0, SEEK_END);
length = ftell(f);
length = (size_t)ftell(f);
fseek(f, 0, SEEK_SET);
if (length)
{
@ -37,12 +36,31 @@ static void glfw_error_callback(int errcode, const char *description)
fprintf(stderr, "[GLFW ERROR][ERRCODE %d] %s\n", errcode, description);
}
void set_uniform(GLuint program_id, const char *name, vec4f value)
void set_uniform4f(GLuint program_id, const char *name, vec4f value)
{
GLint location = glGetUniformLocation(program_id, name);
glUniform4f(location, value.x, value.y, value.z, value.w);
}
void set_uniform2f(GLuint program_id, const char *name, vec2f value)
{
GLint location = glGetUniformLocation(program_id, name);
glUniform2f(location, value.x, value.y);
}
void set_uniform4x4f(GLuint program_id, const char *name, mat4f value)
{
GLint location = glGetUniformLocation(program_id, name);
glUniformMatrix4fv(location, 1, GL_TRUE, &value.a0);
}
#define set_uniform(id, name, value) _Generic((value), \
vec4f: set_uniform4f, \
vec2f: set_uniform2f, \
mat4f: set_uniform4x4f)(id, name, value)
int main(void)
{
GLFWwindow *window;
@ -112,12 +130,12 @@ int main(void)
background_color.a = 1.0f;
hexgrid_t grid;
grid.rows = 10;
grid.columns = 10;
grid.rows = 30;
grid.columns = 30;
grid.hexes = calloc(1, sizeof(hex_t) * grid.rows * grid.columns);
// Scale of hexagon relative to screen. A 1:1 hexagon would reach the entire horizontal space
float scale = 1.0f / 5.0f;
float scale = 1.0f / 1.0f;
for (size_t i = 0; i < grid.columns; ++i)
{
@ -126,13 +144,14 @@ int main(void)
// Offset the X and Y coordinates of adjacent hexagons so they do not cut each other
float offset = 0.0f;
if (j % 2)
offset = sint(1.0f/6);
offset = (float)sint(1.0f/6);
grid.hexes[i*grid.rows+j].position.x = (0.0f + j*(1 + cost(1.0f/6)));
grid.hexes[i*grid.rows+j].position.y = (0.0f + i*(sint(1.0f/6))*2.0f) + offset;
grid.hexes[i*grid.rows+j].position.z = 0.0f;
grid.hexes[i*grid.rows+j].position.w = 1.0f;
fprintf(stdout, "Position of hex %ld %ld is %f %f\n", i, j, grid.hexes[i*grid.rows+j].position.x, grid.hexes[i*grid.rows+j].position.y);
log_debug("Position of hex %ld %ld is %f %f\n", i, j, grid.hexes[i*grid.rows+j].position.x, grid.hexes[i*grid.rows+j].position.y);
}
}
@ -184,8 +203,63 @@ int main(void)
//glBindBuffer(GL_ARRAY_BUFFER, 0);
//glBindVertexArray(0);
camera_t camera = {};
camera.near = -0.1f;
camera.far = 1.0f;
camera.left = 0.0f;
camera.right = 600.0f;
camera.top = 0.0f;
camera.bottom = 600.0f;
while (!glfwWindowShouldClose(window))
{
// Camera logic
if (glfwGetKey(window, GLFW_KEY_A))
{
camera.right -= (camera.right - camera.left) * 0.01f;
camera.left -= (camera.right - camera.left) * 0.01f;
}
if (glfwGetKey(window, GLFW_KEY_D))
{
camera.right += (camera.right - camera.left) * 0.01f;
camera.left += (camera.right - camera.left) * 0.01f;
}
if (glfwGetKey(window, GLFW_KEY_W))
{
camera.top += (camera.bottom - camera.top) * 0.01f;
camera.bottom += (camera.bottom - camera.top) * 0.01f;
}
if (glfwGetKey(window, GLFW_KEY_S))
{
camera.top -= (camera.bottom - camera.top) * 0.01f;
camera.bottom -= (camera.bottom - camera.top) * 0.01f;
}
if (glfwGetKey(window, GLFW_KEY_Q))
{
float offset = (camera.right - camera.left)*0.02f;
camera.right -= offset;
camera.left += offset;
camera.top += offset;
camera.bottom -= offset;
}
if (glfwGetKey(window, GLFW_KEY_E))
{
float offset = (camera.right - camera.left)*0.05f;
camera.right += offset;
camera.left -= offset;
camera.top -= offset;
camera.bottom += offset;
}
if (glfwGetKey(window, GLFW_KEY_R))
{
camera.near = -0.1f;
camera.far = 1.0f;
camera.left = 0.0f;
camera.right = 400.0f;
camera.top = 0.0f;
camera.bottom = 400.0f;
}
int width, height;
glfwGetFramebufferSize(window, &width, &height);
glViewport(0, 0, width, height);
@ -194,10 +268,19 @@ int main(void)
glClear(GL_COLOR_BUFFER_BIT);
glUseProgram(shader_program);
//glPolygonMode(GL_FRONT_AND_BACK, GL_LINE);
mat4f camera_matrix = ortho_matrix(camera.left, camera.right, camera.top, camera.bottom, camera.near, camera.far, width, height);
set_uniform(shader_program, "camera", camera_matrix);
vec2f window_size = { .x = (float)width, .y = (float)height };
set_uniform(shader_program, "window_size", window_size);
// For debugging
float aux;
glGetUniformfv(shader_program, glGetUniformLocation(shader_program, "window_size"), &aux);
for (size_t i = 0; i < grid.rows * grid.columns; ++i)
{
@ -207,6 +290,7 @@ int main(void)
hex_color.g = (float)i / (grid.rows * grid.columns);
hex_color.b = (float)i / (grid.rows * grid.columns);
hex_color.a = 1.0f;
set_uniform(shader_program, "uniform_color", hex_color);
glBindVertexArray(grid.hexes[i].vao);
@ -215,6 +299,7 @@ int main(void)
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, grid.hexes[i].ebo);
glDrawElements(GL_TRIANGLES, 3*6, GL_UNSIGNED_INT, 0);
}
glfwPollEvents();
glfwSwapBuffers(window);
}

8
shaders/vertex.glsl
View file

@ -1,14 +1,20 @@
#version 330 core
layout (location = 0) in vec3 pos;
uniform vec4 uniform_color;
uniform mat4 camera;
uniform vec2 window_size;
out vec4 vertex_color;
const mat4 to_draw_coordinates_matrix = mat4(
1., 0., 0., 0.,
0., -1., 0., 0.,
0., 0., 1., 0.,
-1, 1, 0, 1);
void main()
{
gl_Position = to_draw_coordinates_matrix*vec4(pos, 1.0f);
float aspect_ratio = window_size.x / window_size.y;
mat4 scaling_matrix = mat4(1.0);
scaling_matrix[1][1] = aspect_ratio;
gl_Position = camera*scaling_matrix*to_draw_coordinates_matrix*vec4(pos, 1.0f);
vertex_color = uniform_color;
}