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#include "../../../shared_cpp/OrthographicRenderer.h"
#include "../../../shared_cpp/types.h"
#include "../../../shared_cpp/WebglContext.h"
#include "../../../shared_cpp/mathlib.h"
#include "../../../shared_cpp/MainLoop.h"
#include <cstdio>
#include <cmath>
#include <emscripten/html5.h>
#include <unistd.h>
#include <pthread.h>
#include <cmath>
#include <cfloat>
struct Rigidbody {
Vector2 force = { 0, 0 };
Vector2 velocity = { 0, 0 };
Vector2 position = { 0, 0 };
float32 mass = 1.f;
void reset() {
force = { 0, 0 };
velocity = { 0, 0 };
}
void applyForce(Vector2 f) {
force += f;
}
void applyGravity(float32 deltaTimeSeconds) {
velocity += (Vector2 { 0.f, -50.f } * deltaTimeSeconds);
}
void update(float32 deltaTimeSeconds) {
applyGravity(deltaTimeSeconds);
Vector2 acceleration = force / mass;
velocity += (acceleration * deltaTimeSeconds);
position += (velocity * deltaTimeSeconds);
force = Vector2 { 0.f, 0.f };
}
};
struct Rectangle {
OrthographicShape shape;
Rigidbody body;
void load(OrthographicRenderer* renderer, Vector4 color, float32 width, float32 height) {
color = color.toNormalizedColor();
float32 halfWidth = width / 2.f;
float32 halfHeight = height / 2.f;
OrthographicVertex vertices[6];
vertices[0].position = Vector2 { -halfWidth, -halfHeight };
vertices[1].position = Vector2 { -halfWidth, halfHeight };
vertices[2].position = Vector2 { halfWidth, halfHeight };
vertices[3].position = Vector2 { -halfWidth, -halfHeight };
vertices[4].position = Vector2 { halfWidth, -halfHeight };
vertices[5].position = Vector2 { halfWidth, halfHeight };
for (int32 i = 0; i < 6; i++) {
vertices[i].color = color;
}
shape.load(vertices, 6, renderer);
body.reset();
}
void update(float32 dtSeconds) {
body.update(dtSeconds);
shape.model = Mat4x4().translateByVec2(body.position);
}
void render(OrthographicRenderer* renderer) {
shape.render(renderer);
}
void unload() {
shape.unload();
}
};
EM_BOOL onPlayClicked(int eventType, const EmscriptenMouseEvent* mouseEvent, void* userData);
EM_BOOL onStopClicked(int eventType, const EmscriptenMouseEvent* mouseEvent, void* userData);
void load();
void update(float32 time, void* userData);
void unload();
WebglContext context;
OrthographicRenderer renderer;
MainLoop mainLoop;
Rectangle rectangle;
int main() {
context.init("#gl_canvas");
emscripten_set_click_callback("#gl_canvas_play", NULL, false, onPlayClicked);
emscripten_set_click_callback("#gl_canvas_stop", NULL, false, onStopClicked);
return 0;
}
void load() {
renderer.load(&context);
rectangle.load(&renderer, Vector4 { 55.f, 235.f, 35.f, 255.f }, 32.f, 32.f);
rectangle.body.position = Vector2 { context.width / 3.f, context.height / 3.f };
rectangle.body.velocity = Vector2 { 100.f, 250.f };
mainLoop.run(update);
}
void update(float32 deltaTimeSeconds, void* userData) {
rectangle.update(deltaTimeSeconds);
// Check collisions with walls so we don't go out of the scene. Simply reflect here.
if (rectangle.body.position.x <= 0.f) {
rectangle.body.position.x = 0.f;
rectangle.body.velocity = rectangle.body.velocity - Vector2 { 1.f, 0.f } * (2 * (rectangle.body.velocity.dot(Vector2 { 1.f, 0.f })));
}
if (rectangle.body.position.y <= 0.f) {
rectangle.body.position.y = 0.f;
rectangle.body.velocity = rectangle.body.velocity - Vector2 { 0.f, 1.f } * (2 * (rectangle.body.velocity.dot(Vector2 { 0.f, 1.f })));
}
if (rectangle.body.position.x >= 640.f) {
rectangle.body.position.x = 640.f;
rectangle.body.velocity = rectangle.body.velocity - Vector2 { -1.f, 0.f } * (2 * (rectangle.body.velocity.dot(Vector2{ -1.f, 0.f })));
}
if (rectangle.body.position.y >= 480.f) {
rectangle.body.position.y = 480.f;
rectangle.body.velocity = rectangle.body.velocity - Vector2 { 0.f, -1.f } * (2 * (rectangle.body.velocity.dot(Vector2 { 0.f, -1.f }))) ;
}
// Renderer
renderer.render();
rectangle.render(&renderer);
}
void unload() {
mainLoop.stop();
renderer.unload();
rectangle.unload();
}
//
// Interactions with DOM handled below
//
EM_BOOL onPlayClicked(int eventType, const EmscriptenMouseEvent* mouseEvent, void* userData) {
printf("Play clicked\n");
load();
return true;
}
EM_BOOL onStopClicked(int eventType, const EmscriptenMouseEvent* mouseEvent, void* userData) {
printf("Stop clicked\n");
unload();
return true;
}
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