more stuff

.gitignore

@@ -6,3 +6,6 @@
 *.LNK
 *.o
 *.exe
+*.err
+*.bak
+*.lib

game.c

@@ -101,6 +101,10 @@ void buildArena() {
   }
 }
 
+#define RABBIT_MOTION_DRAG (2)
+#define RABBIT_MOTION_ACCELERATION (5)
+#define RABBIT_MOTION_MAX_SPEED (12)
+
 int rabbitPosition[2] = { 60, 60 };
 int oldRabbitPosition[2] = { 60, 60 };
 int rabbitLimits[2][2] = {
@@ -108,31 +112,27 @@ int rabbitLimits[2][2] = {
   { 180, 180 }
 };
 
-#define RABBIT_MOTION_DRAG (2)
-#define RABBIT_MOTION_ACCELERATION (5)
-#define RABBIT_MOTION_MAX_SPEED (12)
-
 signed char rabbitVelocity[2] = { 0, 0 };
 
 struct MouseStatus mouseStatus;
 char mousePosition[2] = { 0, 0 };
 char oldMousePosition[2] = { 0, 0 };
 
-void setupRabbitDrawing() {
-  rabbit.x = rabbitPosition[0];
-  rabbit.y = rabbitPosition[1];
-}
-
-void setupMouseDrawing() {
-  mouse.x = mousePosition[0];
-  mouse.y = mousePosition[1];
-}
+char mouseDotPosition[2] = { 0, 0 };
+char oldMouseDotPosition[2] = { 0, 0 };
 
 void renderMouse() {
+  mouse.x = mousePosition[0];
+  mouse.y = mousePosition[1];
+
   drawSprite(&mouse);
+  drawPixel(mouseDotPosition[0], mouseDotPosition[1], 2);
 }
 
 void renderRabbit() {
+  rabbit.x = rabbitPosition[0];
+  rabbit.y = rabbitPosition[1];
+
   drawSprite(&rabbit);
 }
 
@@ -196,8 +196,6 @@ void drawOnlyArena() {
   int leftTileX, rightTileX,
       topTileY, bottomTileY;
 
-  char buffer[20];
-
   leftTileX = bounds.left / TILE_SIZE;
   rightTileX = bounds.right / TILE_SIZE;
   topTileY = bounds.top / TILE_SIZE;
@@ -214,6 +212,12 @@ void drawOnlyMouseArena() {
   mouse.y = oldMousePosition[1];
   getSpriteBounds(&mouse, &bounds);
   drawOnlyArena();
+
+  bounds.top = oldMouseDotPosition[1];
+  bounds.bottom = oldMouseDotPosition[1];
+  bounds.left = oldMouseDotPosition[0];
+  bounds.right = oldMouseDotPosition[0];
+  drawOnlyArena();
 }
 
 void drawOnlyRabbitArena() {
@@ -231,6 +235,12 @@ void calculateTargetAngle() {
   float distanceX, distanceY;
   float angle;
 
+  oldMouseDotPosition[0] = mouseDotPosition[0];
+  oldMouseDotPosition[1] = mouseDotPosition[1];
+
+  mouseDotPosition[0] = mouseStatus.xPosition;
+  mouseDotPosition[1] = mouseStatus.yPosition;
+
   distanceX = mouseStatus.xPosition - rabbitPosition[0];
   distanceY = mouseStatus.yPosition - rabbitPosition[1];
 
@@ -268,6 +278,7 @@ int main(void) {
   setVGAColors(vgaColors, 256);
 
   activateMouse(&mouseStatus);
+  limitMouseArea(0, 0, 199, 199);
 
   buildArena();
 
@@ -279,8 +290,6 @@ int main(void) {
 
     drawOnlyRabbitArena();
     drawOnlyMouseArena();
-    setupRabbitDrawing();
-    setupMouseDrawing();
     renderRabbit();
     renderMouse();
 
@@ -290,8 +299,7 @@ int main(void) {
 
     waitEndVbl();
 
-
-    if (mouseStatus.leftButtonDown) { keepRunning = 0; }
+    if (keyboardKeydownState.KEY_ESC) { keepRunning = 0; }
   }
 
   // states:

makefile

@@ -10,7 +10,7 @@ system/system.lib: .SYMBOLIC
 .c.o:
 	wcc386 -q -bt=dos $<
 
-game.exe: $(obj)
+game.exe: $(obj) system/system.lib
   wcl386 -q -bt=dos -l=dos4g $(obj) system/system.lib
 
 clean: .SYMBOLIC

system/keyboard.c

@@ -13,6 +13,7 @@ void populateKeyboardKeydownState() {
   keyboardKeydownState.KEY_A = keystateBits[3] & 0x40;
   keyboardKeydownState.KEY_S = keystateBits[3] & 0x80;
   keyboardKeydownState.KEY_D = keystateBits[4] & 0x01;
+  keyboardKeydownState.KEY_ESC = keystateBits[0] & 0x02;
 }
 
 void far interrupt keyboardHandler(void) {

system/keyboard.h

@@ -10,6 +10,7 @@ struct KeyboardKeydownState {
   byte KEY_A;
   byte KEY_S;
   byte KEY_D;
+  byte KEY_ESC;
 };
 
 extern struct KeyboardKeydownState keyboardKeydownState;

system/mouse_io.c

@@ -6,6 +6,21 @@
 
 struct MouseStatus *_status;
 
+int limitMouseArea(int sx, int sy, int ex, int ey) {
+  union REGS regs;
+
+  // set horiz and vert range
+  regs.w.ax = 0x07;
+  regs.w.cx = sx;
+  regs.w.dx = ex;
+  int386(MOUSE_DRIVER_INTERRUPT, &regs, &regs);
+
+  regs.w.ax = 0x08;
+  regs.w.cx = sy;
+  regs.w.dx = ey;
+  int386(MOUSE_DRIVER_INTERRUPT, &regs, &regs);
+}
+
 /**
  * Ensure this is called after setting the desired video mode.
  */
@@ -22,16 +37,7 @@ int activateMouse(struct MouseStatus *status) {
     status->isActive = regs.w.ax;
     status->buttonCount = regs.w.bx;
 
-    // set horiz and vert range
-    regs.w.ax = 0x07;
-    regs.w.cx = 0;
-    regs.w.dx = VGA_DISPLAY_WIDTH - 1;
-    int386(MOUSE_DRIVER_INTERRUPT, &regs, &regs);
-
-    regs.w.ax = 0x08;
-    regs.w.cx = 0;
-    regs.w.dx = VGA_DISPLAY_HEIGHT - 1;
-    int386(MOUSE_DRIVER_INTERRUPT, &regs, &regs);
+    limitMouseArea(0, 0, VGA_DISPLAY_WIDTH - 1, VGA_DISPLAY_HEIGHT - 1);
   }
 
   _status = status;

system/mouse_io.h

@@ -15,4 +15,5 @@ struct MouseStatus {
 #define MOUSE_DRIVER_READ_STATE (0x03);
 
 int activateMouse(struct MouseStatus *);
+int limitMouseArea(int sx, int sy, int ex, int ey);
 void readMouse(struct MouseStatus *);

system/vga.c

@@ -50,6 +50,10 @@ void buildSpriteFromSpritesheet(
   spriteRender->transparentColor = spritesheetImage->transparentColor;
 }
 
+void drawPixel(int x, int y, int color) {
+  drawBuffer[y * VGA_DISPLAY_WIDTH + x] = color;
+}
+
 void drawSprite(struct SpriteRender* sprite) {
   int x, y;
   byte pixel;

system/vga.h

@@ -35,6 +35,8 @@ struct SpriteBounds {
   int left;
 };
 
+void drawPixel(int x, int y, int color);
+
 void drawSprite(struct SpriteRender *sprite);
 void buildSpriteFromSpritesheet(struct BMPImage*, struct SpriteRender*, int, int, int, int);
 void getSpriteBounds(struct SpriteRender *sprite, struct SpriteBounds *bounds);