From 653d4697d9f630ba2fc52eba9fd966a409ef89fe Mon Sep 17 00:00:00 2001
From: Oshgnacknak <osh@oshgnacknak.de>
Date: Wed, 29 Dec 2021 13:43:41 +0100
Subject: [PATCH] Can jump

---
 Makefile   |   6 ++
 hophop.cpp | 191 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 197 insertions(+)
 create mode 100644 Makefile
 create mode 100644 hophop.cpp

diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..6dd3d3e
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,6 @@
+LIBS=glfw3 glew
+CPPFLAGS=-Wall -Wextra $(shell pkg-config --cflags $(LIBS)) -ggdb -std=c++20
+LDLIBS=$(shell pkg-config --libs $(LIBS)) -lm
+
+hophop: hophop.cpp
+	$(CXX) hophop.cpp -o hophop $(CPPFLAGS) $(LDLIBS)
diff --git a/hophop.cpp b/hophop.cpp
new file mode 100644
index 0000000..8f74892
--- /dev/null
+++ b/hophop.cpp
@@ -0,0 +1,191 @@
+#define OSH_H_IMPLEMENTATION
+#include "osh.h"
+
+#include <GL/glew.h>
+#include <GLFW/glfw3.h>
+
+#define GRAVITY 0.05
+#define FLOOR_HEIGHT -0.9
+#define JUMP_TIMEOUT 0.14
+#define JUMP_FORCE 0.3
+#define DRAG 0.98
+#define PLAYER_RADIUS 0.02
+
+#define PLAYER_COLOR 1.0, 1.0, 1.0
+#define FLOOR_COLOR 0.15, 0.05, 0.05
+#define BACKGROUND_COLOR 0.05, 0.05, 0.05, 1.0
+
+void onError(const int error, const char* description) {
+    (void) error;
+    osh::panic("GLFW error:", description);
+}
+
+struct Vector2 {
+    double x, y;
+
+    Vector2(double x = 0, double y = 0) : x(x), y(y) {}
+
+    Vector2 conjugate() {
+        return {x, -y};
+    }
+    
+    Vector2 operator*(double d) {
+        return {x*d, y*d};
+    }
+
+    Vector2 operator*=(double d) {
+        x *= d;
+        y *= d;
+        return *this;
+    }
+
+    Vector2 operator+(Vector2 v) {
+        return {x+v.x, y+v.y};
+    }
+
+    Vector2 operator+=(Vector2 v) {
+        x += v.x;
+        y += v.y;
+        return *this;
+    }
+
+    Vector2 operator-(Vector2 v) {
+        return {x-v.x, y-v.y};
+    }
+
+    Vector2 operator-=(Vector2 v) {
+        x -= v.x;
+        y -= v.y;
+        return *this;
+    }
+};
+
+void print1(osh::Formatter auto& fmt, const Vector2& v) {
+    osh::printp(fmt, '(', v.x, ", ", v.y, ')');
+}
+
+void onResize(GLFWwindow* window, int width, int height) {
+        glfwGetFramebufferSize(window, &width, &height);
+        glViewport(0, 0, width, height);
+
+        glLoadIdentity();
+        glOrtho(
+            -double(width) / height, double(width) / height,
+            -1, 1,
+            0, 1);
+}
+
+void fillRect(Vector2 pos, Vector2 size) {
+    glBegin(GL_POLYGON);
+
+    glVertex2d(pos.x,           pos.y);
+    glVertex2d(pos.x + size.x,  pos.y);
+    glVertex2d(pos.x + size.x,  pos.y - size.y);
+    glVertex2d(pos.x,           pos.y - size.y);
+
+    glEnd();
+}
+
+void drawPoint(Vector2 pos, double radius) {
+    glPointSize(radius);
+    glBegin(GL_POINTS);
+    glVertex2d(pos.x, pos.y);
+    glEnd();
+}
+
+struct Player {
+    double jumpTimeout = 0;
+    Vector2 pos, vel, acc, size;
+
+    Player() : size(PLAYER_RADIUS, PLAYER_RADIUS) {}
+
+    void push(Vector2 force) {
+        acc += force;
+    }
+
+    void jump() {
+        vel.y = JUMP_FORCE;
+        jumpTimeout = JUMP_TIMEOUT;
+    }
+
+    void update(double dt) {
+        if (jumpTimeout > 0) {
+            push({0, JUMP_FORCE});
+            jumpTimeout -= dt;
+        }
+
+        vel += acc;
+        vel *= DRAG;
+        acc = {0, 0};
+
+        pos += vel * dt;
+        pos.y = osh::max(pos.y, FLOOR_HEIGHT + size.y);
+    }
+
+    void draw() {
+        glColor3d(PLAYER_COLOR);
+        fillRect(pos - size.conjugate(), size*2);
+
+        glColor3d(1.0, 0, 0);
+        drawPoint(pos, 10);
+    }
+};
+
+Player player;
+
+void onKey(GLFWwindow* window, int key, int scancode, int action, int mods) {
+    (void) window;
+    (void) scancode;
+    (void) mods;
+
+    if (action == GLFW_PRESS) {
+        if (key == GLFW_KEY_SPACE) {
+            player.jump();
+        }
+    }
+}
+
+int main(void) {
+    glfwSetErrorCallback(onError);
+
+    glfwInit();
+
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 2);
+    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 0);
+    GLFWwindow* window = glfwCreateWindow(640, 480, "HopHop", NULL, NULL);
+
+    glfwSetKeyCallback(window, onKey);
+    glfwSetWindowSizeCallback(window, onResize);
+
+    glfwMakeContextCurrent(window);
+
+    if (glewInit() != GLEW_OK) {
+        osh::panic("glewInit() failed");
+    }
+
+    double last = glfwGetTime();
+    while (!glfwWindowShouldClose(window)) {
+        double now = glfwGetTime();
+        double dt = now - last;
+
+        glfwPollEvents();
+
+        glClearColor(BACKGROUND_COLOR);
+        glClear(GL_COLOR_BUFFER_BIT);
+
+        player.push({0, -GRAVITY});
+        player.update(dt);
+
+        player.draw();
+
+        glColor3d(FLOOR_COLOR);
+        fillRect({ -1, FLOOR_HEIGHT }, {2, 2});
+
+        glfwSwapBuffers(window);
+        last = now;
+    }
+
+    glfwDestroyWindow(window);
+    glfwTerminate();
+    return 0;
+}