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path: root/frontend/2d/_collisions/rectangle_line/main.cpp
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-rw-r--r--frontend/2d/_collisions/rectangle_line/main.cpp326
1 files changed, 0 insertions, 326 deletions
diff --git a/frontend/2d/_collisions/rectangle_line/main.cpp b/frontend/2d/_collisions/rectangle_line/main.cpp
deleted file mode 100644
index 25e124c..0000000
--- a/frontend/2d/_collisions/rectangle_line/main.cpp
+++ /dev/null
@@ -1,326 +0,0 @@
-#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>
-
-struct Rigidbody {
- Vector2 force = { 0, 0 };
- Vector2 velocity = { 0, 0 };
- Vector2 position = { 0, 0 };
- float32 rotationalVelocity = 0.f;
- float32 rotation = 0.f;
- float32 mass = 1.f;
- float32 cofOfRestition = 1.f;
- float32 momentOfInertia = 0.f;
-
- void reset() {
- force = { 0, 0 };
- velocity = { 0, 0 };
- rotationalVelocity = 0.f;
- rotation = 0.f;
- }
-
- 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 };
-
- rotation += (rotationalVelocity * deltaTimeSeconds);
- }
-
- void setMomentOfInertia(float32 moi) {
- momentOfInertia = moi;
- }
-};
-
-struct IntersectionResult {
- bool intersect = false;
- Vector2 collisionNormal;
- Vector2 relativeVelocity;
- Vector2 firstPointOfApplication;
- Vector2 secondPointOfApplication;
-};
-
-struct Rectangle {
- OrthographicShape shape;
- Rigidbody body;
- Vector4 color;
- float32 width = 0.f;
- float32 height = 0.f;
-
- void load(OrthographicRenderer* renderer, Vector4 inColor, float32 inWidth, float32 inHeight) {
- color = inColor.toNormalizedColor();
- width = inWidth;;
- height = inHeight;
-
- 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();
- body.momentOfInertia = (1.f / 3.f) * body.mass * (width + height * height * height);
- }
-
- void update(float32 dtSeconds) {
- body.update(dtSeconds);
- shape.model = Mat4x4().translateByVec2(body.position).rotate2D(body.rotation);
- }
-
- void render(OrthographicRenderer* renderer) {
- shape.render(renderer);
- }
-
- void unload() {
- shape.unload();
- }
-};
-
-struct LineSegment {
- OrthographicShape shape;
- Rigidbody body;
- Vector2 start;
- Vector2 end;
- float32 length;
- Vector2 normal;
- OrthographicVertex vertices[2];
-
- void load(OrthographicRenderer* renderer, Vector4 color, Vector2 inStart, Vector2 inEnd) {
- start = inStart;
- end = inEnd;
- length = (start - end).length();
- vertices[0].position = start;
- vertices[0].color = color;
- vertices[1].position = end;
- vertices[1].color = color;
- normal = (end - start).getPerp().normalize();
- shape.load(vertices, 2, renderer);
-
- body.reset();
- body.mass = 10000000000000.f;
- body.cofOfRestition = 1.f;
- body.rotationalVelocity = 0;
- body.velocity = Vector2();
- body.momentOfInertia = body.mass * (length / 2.f);
- }
-
- void render(OrthographicRenderer* renderer) {
- shape.render(renderer, GL_LINES);
- }
-
- void unload() {
- shape.unload();
- }
-
- Vector2 getPointOnLine(float32 t) {
- return {
- start.x + (end.x - start.x) * t,
- start.y + (end.y - start.y) * t,
- };
- }
-
- Vector2 getNormal() {
- return (end - start).getPerp().normalize();
- }
-};
-
-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;
-LineSegment segmentList[4];
-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);
-
- segmentList[0].load(&renderer, Vector4().fromColor(191, 251, 146, 255.f), Vector2 { 50.f, 0.f }, Vector2 { 50.f, static_cast<float>(context.height) });
- segmentList[1].load(&renderer, Vector4().fromColor(159, 224, 210, 255.f), Vector2 { context.width - 50.f, 0.f }, Vector2 { context.width - 50.f, static_cast<float>(context.height) });
- segmentList[2].load(&renderer, Vector4().fromColor(248, 255, 156, 255.f), Vector2 { 50.f, 50.f }, Vector2 { context.width - 50.f, 150.f });
- segmentList[3].load(&renderer, Vector4().fromColor(205, 178, 214, 255.f), Vector2 { 50.f, 150.f }, Vector2 { context.width - 50.f, 50.f });
-
- rectangle.load(&renderer, Vector4 { 230.f, 182.f, 35.f, 255.f }, 64.f, 32.f);
- rectangle.body.position = Vector2 { context.width / 3.f, context.height - 100.f };
-
- mainLoop.run(update);
-}
-
-float32 getDistancePointToLine(Vector2 point, LineSegment* segment) {
- float32 xLength = segment->end.x - segment->start.x;
- float32 yLength = segment->end.y - segment->start.y;
- return fabs(xLength * (segment->start.y - point.y) - (segment->start.x - point.x) * yLength)
- / sqrtf((xLength * xLength) + (yLength * yLength));
-}
-
-const float32 EPSILON = 1.f;
-IntersectionResult getIntersection(Rectangle* rectangle, LineSegment* segment) {
- IntersectionResult ir;
-
- float32 halfWidth = rectangle->width / 2.f;
- float32 halfHeight = rectangle->height / 2.f;
-
- Vector2 bottomLeft = rectangle->shape.model * Vector2 { -halfWidth, -halfHeight };
- Vector2 topLeft = rectangle->shape.model * Vector2 { -halfWidth, halfHeight };
- Vector2 bottomRight = rectangle->shape.model * Vector2 { halfWidth, -halfHeight };
- Vector2 topRight = rectangle->shape.model * Vector2 { halfWidth, halfHeight };
-
- Vector2 collisionPoint;
-
- if (getDistancePointToLine(bottomLeft, segment) <= EPSILON) {
- ir.intersect = true;
- collisionPoint = bottomLeft;
- } else if (getDistancePointToLine(topLeft, segment) <= EPSILON) {
- ir.intersect = true;
- collisionPoint = topLeft;
- } else if (getDistancePointToLine(bottomRight, segment) <= EPSILON) {
- ir.intersect = true;
- collisionPoint = bottomRight;
- } else if (getDistancePointToLine(topRight, segment) <= EPSILON) {
- ir.intersect = true;
- collisionPoint = topRight;
- } else {
- ir.intersect = false;
- return ir;
- }
-
- ir.collisionNormal = segment->getNormal();
- ir.relativeVelocity = rectangle->body.velocity - segment->body.velocity;
- ir.firstPointOfApplication = (collisionPoint - rectangle->body.position);
- ir.secondPointOfApplication = collisionPoint - segment->getPointOnLine(0.5f);
-
- return ir;
-}
-
-void resolveCollision(Rigidbody* first, Rigidbody* second, IntersectionResult* ir) {
- Vector2 relativeVelocity = ir->relativeVelocity;
- Vector2 collisionNormal = ir->collisionNormal;
- Vector2 firstPerp = ir->firstPointOfApplication.getPerp();
- Vector2 secondPerp = ir->secondPointOfApplication.getPerp();
- float32 firstPerpNorm = firstPerp.dot(collisionNormal);
- float32 sndPerpNorm = secondPerp.dot(collisionNormal);
-
- float32 cofOfRestition = (first->cofOfRestition + second->cofOfRestition) / 2.f;
- float32 numerator = (relativeVelocity * (-1 * (1.f + cofOfRestition))).dot(collisionNormal);
- float32 linearDenomPart = collisionNormal.dot(collisionNormal * (1.f / first->mass + 1.f / second->mass));
- float32 rotationalDenomPart = (firstPerpNorm * firstPerpNorm) / first->momentOfInertia + (sndPerpNorm * sndPerpNorm) / second->momentOfInertia;
-
- float32 impulseMagnitude = numerator / (linearDenomPart + rotationalDenomPart);
- first->velocity = first->velocity + (collisionNormal * (impulseMagnitude / first->mass));
- second->velocity = second->velocity - (collisionNormal * (impulseMagnitude / second->mass));
- first->rotationalVelocity = first->rotationalVelocity + firstPerp.dot(collisionNormal * impulseMagnitude) / first->momentOfInertia;
- second->rotationalVelocity = second->rotationalVelocity - secondPerp.dot(collisionNormal * impulseMagnitude) / second->momentOfInertia;
-}
-
-void update(float32 deltaTimeSeconds, void* userData) {
- // Update
- Rectangle rectCopy = rectangle;
- rectangle.update(deltaTimeSeconds);
-
- for (int32 segmentIndex = 0; segmentIndex < 4; segmentIndex++) {
- IntersectionResult ir = getIntersection(&rectangle, &segmentList[segmentIndex]);
- if (!ir.intersect) {
- continue;
- }
-
- // Handle collison here
- IntersectionResult irCopy = ir;
- float32 copyDt = deltaTimeSeconds;
-
- do {
- ir = irCopy;
- rectangle = rectCopy;
- copyDt = copyDt /= 2.f;
-
- rectangle.update(copyDt);
- irCopy = getIntersection(&rectangle, &segmentList[segmentIndex]);
-
- if (copyDt <= 0.f) {
- printf("Error: Should not be happening.\n");
- break;
- }
-
- } while (irCopy.intersect);
-
- printf("Found intersection at timestamp: %f\n", copyDt);
-
- resolveCollision(&rectangle.body, &segmentList[segmentIndex].body, &ir);
- float32 frameTimeRemaining = deltaTimeSeconds - copyDt;
-
- update(frameTimeRemaining, userData);
- return;
- }
-
- // Renderer
- renderer.render();
- rectangle.render(&renderer);
- for (int32 segmentIndex = 0; segmentIndex < 4; segmentIndex++) {
- segmentList[segmentIndex].render(&renderer);
- }
-}
-
-void unload() {
- mainLoop.stop();
- renderer.unload();
- for (int32 segmentIndex = 0; segmentIndex < 4; segmentIndex++) {
- segmentList[segmentIndex].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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