messing with assembler

arena.c

@@ -55,8 +55,8 @@ void renderArenaTile(int x, int y) {
       break;
   }
 
-  target->x = x * 20;
+  target->x = x * TILE_SIZE;
-  target->y = y * 20;
+  target->y = y * TILE_SIZE;
 
   drawSprite(target);
 }

const.h

@@ -22,3 +22,4 @@
 #define RAD2DEG (180/3.14159)
 #define DEG2RAD (3.14159/180)
 
+#define ENEMY_MAX_COUNT (20)

game.c

@@ -1,6 +1,8 @@
 #include <stdio.h>
 #include <math.h>
 #include <conio.h>
+#include <stdlib.h>
+#include <time.h>
 
 #include "system/vga.h"
 #include "system/keyboard.h"
@@ -15,7 +17,7 @@
 struct BMPImage spritesheetImage;
 struct VGAColor vgaColors[256];
 
-struct SpriteRender rabbit, mouse, bullet;
+struct SpriteRender rabbit, mouse, bullet, enemy;
 struct RabbitPosition rabbitPosition = {
   .rabbitPosition = { 60, 60 },
   .rabbitLimits = { { 20, 20 }, { 180, 180 } },
@@ -24,11 +26,13 @@ struct RabbitPosition rabbitPosition = {
   .mouseDotPosition = { 0, 0 }
 };
 
+struct EnemyPosition enemyPosition[ENEMY_MAX_COUNT];
+
 struct BulletPosition rabbitBulletPosition[RABBIT_BULLET_LIMIT];
 struct RabbitWeaponry rabbitWeaponry;
 
 void setupRabbitBullets() {
-  char i;
+  int i;
 
   for (i = 0; i < RABBIT_BULLET_LIMIT; ++i) {
     rabbitBulletPosition[i].isActive = 0;
@@ -38,6 +42,15 @@ void setupRabbitBullets() {
   rabbitWeaponry.cooldown = 0;
 }
 
+void setupEnemies() {
+  int i;
+
+  for (i = 0; i < ENEMY_MAX_COUNT; ++i) {
+    enemyPosition[i].isActive = 0;
+    enemyPosition[i].willBeInactive = 0;
+  }
+}
+
 void attemptToFireRabbitBullet() {
   char okToFire = 0, availableBullet, i;
   signed char doubleVelocityX, doubleVelocityY;
@@ -99,6 +112,62 @@ void advanceRabbitBullets() {
   if (rabbitWeaponry.cooldown > 0) rabbitWeaponry.cooldown--;
 }
 
+void detectPlayerBulletToEnemyCollisions() {
+  int bulletIdx, enemyIdx;
+
+  for (bulletIdx = 0; bulletIdx < RABBIT_BULLET_LIMIT; ++bulletIdx) {
+    if (!rabbitBulletPosition[bulletIdx].isActive) continue;
+
+    for (enemyIdx = 0; enemyIdx < ENEMY_MAX_COUNT; ++enemyIdx) {
+      if (!enemyPosition[enemyIdx].isActive) continue;
+
+      // bullets hit enemies if:
+      // * bulletY - bullet_height_start is within 3px of enemy base
+      // * 
+    }
+  }
+}
+
+struct SpawnPointRange {
+  int left, width;
+  int top, height;
+};
+
+struct SpawnPointRange spawnPointRanges[1] = {
+   { .left = 50, .width = 30, .top = 50, .height = 30 }
+};
+
+void maybeSpawnEnemy() {
+  char canSpawn;
+  int i, availableEnemy;
+  int spawnX, spawnY;
+
+  for (i = 0; i < ENEMY_MAX_COUNT; ++i) {
+    if (!enemyPosition[i].isActive) {
+      availableEnemy = i;
+      canSpawn = 1;
+      break;
+    }
+  }
+
+  if (!canSpawn) return;
+
+  spawnX = spawnPointRanges[0].left + rand() % spawnPointRanges[0].width;
+  spawnY = spawnPointRanges[0].top + rand() % spawnPointRanges[0].height;
+
+  enemyPosition[availableEnemy].isActive = 1;
+  enemyPosition[availableEnemy].enemyPosition[0] = spawnX;
+  enemyPosition[availableEnemy].enemyPosition[1] = spawnY;
+}
+
+void setupEnemySprites() {
+  buildSpriteFromSpritesheet(
+    &spritesheetImage,
+    &enemy,
+    0, 20, 16, 16
+  );
+}
+
 void setupRabbitSprites() {
   buildSpriteFromSpritesheet(
     &spritesheetImage,
@@ -145,20 +214,28 @@ void renderRabbit() {
   drawSprite(&rabbit);
 }
 
+void renderEnemies() {
+  int i;
+
+  for (i = 0; i < ENEMY_MAX_COUNT; ++i) {
+    if (!enemyPosition[i].isActive) continue;
+
+    enemy.x = enemyPosition[i].enemyPosition[0];
+    enemy.y = enemyPosition[i].enemyPosition[1];
+
+    drawSprite(&enemy);
+  }
+}
+
 void renderRabbitBullets() {
   char i;
 
-  char buffer[20];
-
   for (i = 0; i < RABBIT_BULLET_LIMIT; ++i) {
     if (!rabbitBulletPosition[i].isActive) continue;
 
     bullet.x = rabbitBulletPosition[i].x;
     bullet.y = rabbitBulletPosition[i].y;
 
-    sprintf(buffer, "%d %d", bullet.x, bullet.y);
-    writeString(buffer, 0, 10);
-
     drawSprite(&bullet);
   }
 }
@@ -185,6 +262,23 @@ void drawOnlyRabbitArena() {
   drawOnlyArena(&bounds);
 }
 
+void drawOnlyEnemiesArena() {
+  int i;
+
+  for (i = 0; i < ENEMY_MAX_COUNT; ++i) {
+    if (!enemyPosition[i].isActive) continue;
+
+    enemy.x = enemyPosition[i].oldEnemyPosition[0];
+    enemy.y = enemyPosition[i].oldEnemyPosition[1];
+    getSpriteBounds(&enemy, &bounds);
+    drawOnlyArena(&bounds);
+
+    if (enemyPosition[i].willBeInactive) {
+      enemyPosition[i].willBeInactive = 0;
+    }
+  }
+}
+
 void drawOnlyRabbitBulletArena() {
   int i;
   for (i = 0; i < RABBIT_BULLET_LIMIT; ++i) {
@@ -201,9 +295,8 @@ void drawOnlyRabbitBulletArena() {
   }
 }
 
-int main(void) {
+int setupGame() {
   FILE *fh;
-  int keepRunning = 1;
 
   installKeyboardHandler();
   initializeDrawBuffer();
@@ -217,6 +310,7 @@ int main(void) {
   setupWallSprites(&spritesheetImage);
   setupRabbitSprites();
   setupRabbitBullets();
+  setupEnemySprites();
 
   setVideoMode(VIDEO_MODE_VGA_256);
   bmp256ColorPaletteToVGAColorPalette(&spritesheetImage, vgaColors);
@@ -227,6 +321,30 @@ int main(void) {
   buildArena();
   clearArenaRedrawRequests();
 
+  srand(time(NULL));
+
+  return 0;
+}
+
+double speedCalcs[200];
+int currentSpeedCalc = 0;
+double averageSpeedCalc;
+clock_t startTime;
+
+extern int doAThing(int);
+#pragma aux (__cdecl) doAThing "doAThing_"
+
+int main(void) {
+  int keepRunning = 1;
+
+  fprintf(stderr, "%d\n", doAThing(1000));
+
+  return 0;
+
+  if (setupGame()) return 1;
+
+  maybeSpawnEnemy();
+
   while (keepRunning) {
     readMouse(&mouseStatus);
     populateKeyboardKeydownState();
@@ -248,10 +366,14 @@ int main(void) {
     advanceRabbitBullets();
 
     drawOnlyRabbitArena();
+    drawOnlyEnemiesArena();
     drawOnlyMouseArena();
     drawOnlyRabbitBulletArena();
+
     redrawArena();
+
     renderRabbit();
+    renderEnemies();
     renderMouse();
     renderRabbitBullets();
 
@@ -269,7 +391,14 @@ int main(void) {
   setVideoMode(VIDEO_MODE_80x25_TEXT);
   uninstallKeyboardHandler();
 
-  fprintf(stderr, "meow\n");
+  averageSpeedCalc = 0;
+  for (currentSpeedCalc = 0; currentSpeedCalc < 200; ++currentSpeedCalc) {
+    averageSpeedCalc += speedCalcs[currentSpeedCalc];
+  }
+
+  averageSpeedCalc /= 200;
+
+  fprintf(stderr, "average: %f\n", averageSpeedCalc);
 
   return 0;
 }

makefile

@@ -1,4 +1,4 @@
-obj = game.o bmpload.o arena.o movement.o
+obj = game.o bmpload.o arena.o movement.o test.o
 
 all: system/system.lib game.exe .SYMBOLIC
 

movement.h

@@ -1,4 +1,5 @@
 #include "system/keyboard.h"
+
 struct RabbitPosition {
   int rabbitPosition[2];
   int oldRabbitPosition[2];
@@ -30,6 +31,15 @@ struct BulletPosition {
   char velocityStep;
 };
 
+struct EnemyPosition {
+  char isActive;
+
+  char willBeInactive;
+
+  int enemyPosition[2];
+  int oldEnemyPosition[2];
+};
+
 void calculateTargetAngle(struct RabbitPosition*, struct MouseStatus*);
 void captureAndLimitMousePosition(struct RabbitPosition*, struct MouseStatus*);
 void handleRabbitMovement(struct RabbitPosition*, struct KeyboardKeydownState*);

system/vga.c

@@ -57,6 +57,7 @@ void drawPixel(int x, int y, int color) {
 void drawSprite(struct SpriteRender* sprite) {
   int x, y;
   byte pixel;
+  int modulo = VGA_DISPLAY_WIDTH - sprite->width;
 
   byte* spriteData = sprite->data;
   byte* drawBufferPos =
@@ -77,7 +78,7 @@ void drawSprite(struct SpriteRender* sprite) {
       drawBufferPos++;
     }
 
-    drawBufferPos += (VGA_DISPLAY_WIDTH - sprite->width);
+    drawBufferPos += modulo;
     spriteData += sprite->modulo;
   }
 }

test.asm

@@ -0,0 +1,19 @@
+PUBLIC doAThing_
+
+.386
+.model flat,c
+
+_TEXT segment byte public 'CODE'
+
+doAThing_:
+  push ebp
+  mov ebp, esp
+
+  mov eax, [ebp + 8]
+
+  pop ebp
+  ret
+
+_TEXT ends
+
+end