collision detection works and is fast. for now.

This commit is contained in:
John Bintz 2024-02-25 12:52:42 -05:00
parent 903835a10a
commit 83c35f68c4
6 changed files with 123 additions and 41 deletions

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@ -5,4 +5,4 @@ void clearArenaRedrawRequests();
void redrawArena();
void drawOnlyArena(struct SpriteBounds *bounds);
void buildArena();
void setupWallSprites(struct BMPImage *);
void setupWallSprites();

133
combat.c
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@ -1,4 +1,5 @@
#include <math.h>
#include <stdio.h>
#include "game.h"
@ -12,7 +13,8 @@ void attemptToFireRabbitBullet(
struct BulletPosition rabbitBulletPosition[]
) {
int okToFire = 0, availableBullet, i;
signed char doubleVelocityX, doubleVelocityY;
signed int doubleVelocityX, doubleVelocityY;
char buffer[20];
if (rabbitWeaponry->cooldown > 0) return;
@ -34,15 +36,15 @@ void attemptToFireRabbitBullet(
rabbitBulletPosition[availableBullet].isActive = 1;
rabbitBulletPosition[availableBullet].willBeInactive = 0;
rabbitBulletPosition[availableBullet].x = rabbitPosition->rabbitPosition[0];
rabbitBulletPosition[availableBullet].y = rabbitPosition->rabbitPosition[1] - RABBIT_BULLET_HEIGHT_START;
rabbitBulletPosition[availableBullet].y = rabbitPosition->rabbitPosition[1];
rabbitBulletPosition[availableBullet].oldX = rabbitBulletPosition[availableBullet].x;
rabbitBulletPosition[availableBullet].oldY = rabbitBulletPosition[availableBullet].y;
rabbitBulletPosition[availableBullet].velocityXSteps[0] = doubleVelocityX / RABBIT_BULLET_VELOCITY;
rabbitBulletPosition[availableBullet].velocityXSteps[1] = doubleVelocityX % RABBIT_BULLET_VELOCITY;
rabbitBulletPosition[availableBullet].velocityXSteps[1] = doubleVelocityX - rabbitBulletPosition[availableBullet].velocityXSteps[0];
rabbitBulletPosition[availableBullet].velocityYSteps[0] = doubleVelocityY / RABBIT_BULLET_VELOCITY;
rabbitBulletPosition[availableBullet].velocityYSteps[1] = doubleVelocityY % RABBIT_BULLET_VELOCITY;
rabbitBulletPosition[availableBullet].velocityYSteps[1] = doubleVelocityY - rabbitBulletPosition[availableBullet].velocityYSteps[0];
rabbitBulletPosition[availableBullet].velocityStep = 0;
}
@ -81,22 +83,12 @@ struct CollisionDetection {
struct CollisionDetection collisionDetection;
int isCollision() {
int result;
if (collisionDetection.sourceEY < collisionDetection.targetSY) return 0;
if (collisionDetection.sourceEX < collisionDetection.targetSX) return 0;
if (collisionDetection.targetEY < collisionDetection.sourceSY) return 0;
if (collisionDetection.targetEX < collisionDetection.sourceSX) return 0;
// first pass: are the hitboxes even close
result = !(
collisionDetection.sourceEY < collisionDetection.targetSY ||
collisionDetection.sourceEX < collisionDetection.targetSX ||
collisionDetection.targetEY < collisionDetection.sourceSY ||
collisionDetection.targetEX < collisionDetection.sourceSX
);
if (!result) return result;
// second pass: check against specific character shaped hitboxes
// these will be generated from the spritesheet generator
return result;
return 1;
}
void populateSourceCollision(struct CompiledSpriteRender *sprite) {
@ -117,31 +109,108 @@ void populateTargetCollision(struct CompiledSpriteRender *sprite) {
collisionDetection.targetEY = bounds.bottom;
}
void handleRabbitToEnemyCollisions(
struct RabbitPosition *rabbitPosition,
struct EnemyPosition enemyPosition[]
) {
int enemyIdx;
// to start: brute force items
// possible performance improvements:
// * grid partitioning
rabbit.x = rabbitPosition->rabbitPosition[0];
rabbit.y = rabbitPosition->rabbitPosition[1];
populateSourceCollision(&rabbit);
for (enemyIdx = 0; enemyIdx < ENEMY_MAX_COUNT; ++enemyIdx) {
if (!enemyPosition[enemyIdx].isActive) continue;
if (enemyPosition[enemyIdx].willBeInactive) continue;
enemy.x = enemyPosition[enemyIdx].enemyPosition[0];
enemy.y = enemyPosition[enemyIdx].enemyPosition[1];
populateTargetCollision(&enemy);
if (isCollision()) {
enemyPosition[enemyIdx].willBeInactive = 1;
}
}
}
int rabbitBulletGrid[4][RABBIT_BULLET_LIMIT];
int enemyGrid[4][ENEMY_MAX_COUNT];
void handleRabbitBulletToEnemyCollisions(
struct BulletPosition rabbitBulletPosition[],
struct EnemyPosition enemyPosition[]
) {
int bulletIdx, enemyIdx;
int bulletIdx, enemyIdx, grid;
int resolvedBulletIdx, resolvedEnemyIdx;
int rabbitGridIndex[4], enemyGridIndex[4];
char buffer[30];
for (grid = 0; grid < 4; ++grid) {
rabbitGridIndex[grid] = 0;
}
// to start: brute force items
// possible performance improvements:
// * horizontal sweep against enemies to rule out enemies to check
for (bulletIdx = 0; bulletIdx < RABBIT_BULLET_LIMIT; ++bulletIdx) {
if (!rabbitBulletPosition[bulletIdx].isActive) continue;
if (rabbitBulletPosition[bulletIdx].willBeInactive) continue;
populateSourceCollision(&bullet);
grid = (
rabbitBulletPosition[bulletIdx].x / (TILE_SIZE * 5)
) + (
(rabbitBulletPosition[bulletIdx].y / (TILE_SIZE * 5)) * 2
);
for (enemyIdx = 0; enemyIdx < ENEMY_MAX_COUNT; ++enemyIdx) {
if (!enemyPosition[enemyIdx].isActive) continue;
if (enemyPosition[enemyIdx].willBeInactive) continue;
rabbitBulletGrid[grid][rabbitGridIndex[grid]++] = bulletIdx;
}
populateTargetCollision(&enemy);
for (grid = 0; grid < 4; ++grid) {
enemyGridIndex[grid] = 0;
}
if (isCollision()) {
enemyPosition[enemyIdx].willBeInactive = 1;
rabbitBulletPosition[bulletIdx].willBeInactive = 1;
break;
for (enemyIdx = 0; enemyIdx < ENEMY_MAX_COUNT; ++enemyIdx) {
if (!enemyPosition[enemyIdx].isActive) continue;
if (enemyPosition[enemyIdx].willBeInactive) continue;
grid = (
enemyPosition[enemyIdx].enemyPosition[0] / (TILE_SIZE * 5)
) + (
(enemyPosition[enemyIdx].enemyPosition[1] / (TILE_SIZE * 5)) * 2
);
enemyGrid[grid][enemyGridIndex[grid]++] = enemyIdx;
}
for (grid = 0; grid < 4; ++grid) {
if (enemyGridIndex[grid] == 0) continue;
for (bulletIdx = 0; bulletIdx < rabbitGridIndex[grid]; ++bulletIdx) {
resolvedBulletIdx = rabbitBulletGrid[grid][bulletIdx];
if (!rabbitBulletPosition[resolvedBulletIdx].isActive) continue;
if (rabbitBulletPosition[resolvedBulletIdx].willBeInactive) continue;
bullet.x = rabbitBulletPosition[resolvedBulletIdx].x;
bullet.y = rabbitBulletPosition[resolvedBulletIdx].y;
populateSourceCollision(&bullet);
for (enemyIdx = 0; enemyIdx < enemyGridIndex[grid]; ++enemyIdx) {
resolvedEnemyIdx = enemyGrid[grid][enemyIdx];
if (!enemyPosition[resolvedEnemyIdx].isActive) continue;
if (enemyPosition[resolvedEnemyIdx].willBeInactive) continue;
enemy.x = enemyPosition[resolvedEnemyIdx].enemyPosition[0];
enemy.y = enemyPosition[resolvedEnemyIdx].enemyPosition[1];
populateTargetCollision(&enemy);
if (isCollision()) {
enemyPosition[resolvedEnemyIdx].willBeInactive = 1;
rabbitBulletPosition[resolvedBulletIdx].willBeInactive = 1;
break;
}
}
}
}

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@ -13,3 +13,8 @@ void handleRabbitBulletToEnemyCollisions(
struct BulletPosition[],
struct EnemyPosition[]
);
void handleRabbitToEnemyCollisions(
struct RabbitPosition*,
struct EnemyPosition[]
);

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@ -10,7 +10,7 @@
#define RABBIT_MOTION_VELOCITY_DECAY (5)
#define RABBIT_BULLET_LIMIT (12)
#define RABBIT_BULLET_VELOCITY (RABBIT_MOTION_ACCELERATION + 2)
#define RABBIT_BULLET_VELOCITY (RABBIT_MOTION_ACCELERATION + 1)
#define RABBIT_BULLET_COOLDOWN (10)
#define RABBIT_BULLET_HEIGHT_START (8)
@ -22,4 +22,4 @@
#define RAD2DEG (180/3.14159)
#define DEG2RAD (3.14159/180)
#define ENEMY_MAX_COUNT (20)
#define ENEMY_MAX_COUNT (50)

18
game.c
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@ -1,3 +1,4 @@
#include <stddef.h>
#include <stdio.h>
#include <math.h>
#include <conio.h>
@ -42,7 +43,7 @@ struct SpawnPointRange {
};
struct SpawnPointRange spawnPointRanges[1] = {
{ .left = 50, .width = 30, .top = 50, .height = 30 }
{ .left = 130, .width = 50, .top = 50, .height = 100 }
};
@ -66,7 +67,6 @@ void setupEnemies() {
}
}
void maybeSpawnEnemy() {
char canSpawn;
int i, availableEnemy;
@ -238,7 +238,7 @@ int setupGame() {
spritesheetImage.transparentColor = 0;
setupWallSprites(&spritesheetImage);
setupWallSprites();
setupRabbitSprites();
setupRabbitBullets();
setupEnemySprites();
@ -286,6 +286,11 @@ void handleCombat() {
&rabbitWeaponry
);
handleRabbitToEnemyCollisions(
&rabbitPosition,
enemyPosition
);
handleRabbitBulletToEnemyCollisions(
rabbitBulletPosition,
enemyPosition
@ -316,23 +321,26 @@ clock_t startTime;
int main(void) {
byte *drawBuffer;
int keepRunning = 1;
int i;
if (setupGame()) return 1;
drawBuffer = getDrawBuffer();
maybeSpawnEnemy();
for (i = 0; i < ENEMY_MAX_COUNT; ++i) {
maybeSpawnEnemy();
}
while (keepRunning) {
readMouse(&mouseStatus);
populateKeyboardKeydownState();
handleMovement();
handleCombat();
handleRedraw();
waitStartVbl();
copyDrawBufferToDisplay();
handleCombat();
waitEndVbl();
if (keyboardKeydownState.KEY_ESC) { keepRunning = 0; }

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@ -31,7 +31,7 @@ void calculateTargetAngle(
// Position the cursor
distanceX = pos->mouseDotPosition[0] - pos->rabbitPosition[0];
distanceY = pos->mouseDotPosition[1] - pos->rabbitPosition[1] - RABBIT_BULLET_HEIGHT_START;
distanceY = pos->mouseDotPosition[1] - pos->rabbitPosition[1];
angle = atan2(distanceY, distanceX) * RAD2DEG + 90;
if (angle < 0) angle += 360;