burnt_casadilla

Rectangle shipBounds = new Rectangle((int)ship.shipPos.X, (int)ship.shipPos.Y, shipSprite.Width, shipSprite.Height);

 

code from my game. Pretty much you just create a rectangle object with the same dimensions as your sprite

 

for (int x = bulletBounds.Count - 1; x > -1; x-- )
            {
                for (int y = alienBounds.Count - 1; y > -1; y--)
                {
                    if (bulletBounds[x].Intersects(alienBounds[y]))
                    {
                        alienPosition.RemoveAt(y);
                        alienBounds.RemoveAt(y);
                        //bulletBounds.RemoveAt(x);
                        hit++;
                        break;
                    }
                }

 

This is my collision method. bulletBounds and alienBounds are both rectangle arrays. You can see how Intersects works also

thanks. those are the kinds of things that help me learn. books dont really explain that

alright i made this from scratch, but the paddles dont move. anyone know whats wrong?

[source lang="csharp"] protected override void Initialize()        {            // TODO: Add your initialization logic here            KeyboardState state = Keyboard.GetState();            if (state.IsKeyDown(Keys.Up))            {                paddle1Pos.Y -= 3;            }            if (state.IsKeyDown(Keys.Down))            {                paddle1Pos.Y += 3;            }            base.Initialize();        }        /// <summary>        /// LoadContent will be called once per game and is the place to load        /// all of your content.        /// </summary>        protected override void LoadContent()        {            // Create a new SpriteBatch, which can be used to draw textures.            spriteBatch = new SpriteBatch(GraphicsDevice);            // TODO: use this.Content to load your game content here            ball = Content.Load<Texture2D>("ball");            paddle = Content.Load<Texture2D>("paddle");        }        /// <summary>        /// UnloadContent will be called once per game and is the place to unload        /// all content.        /// </summary>        protected override void UnloadContent()        {            // TODO: Unload any non ContentManager content here        }        /// <summary>        /// Allows the game to run logic such as updating the world,        /// checking for collisions, gathering input, and playing audio.        /// </summary>        /// <param name="gameTime">Provides a snapshot of timing values.</param>        protected override void Update(GameTime gameTime)        {            int minY = 0;            int minX = 0;            int maxY = 600 - ball.Height;            int maxX = 1000 - ball.Width;            // Allows the game to exit            if (GamePad.GetState(PlayerIndex.One).Buttons.Back == ButtonState.Pressed)                this.Exit();            // TODO: Add your update logic here            ballPos += ballSpeed * (float)gameTime.ElapsedGameTime.TotalSeconds;            if (ballPos.X > maxX)            {                ballPos.X = maxX;                ballSpeed.X *= -1;            }            if (ballPos.X < minX)            {                ballSpeed.X *= -1;                ballPos.X = minX;            }            if (ballPos.Y < minY)            {                ballPos.Y = minY;                ballSpeed.Y *= -1;            }            if (ballPos.Y > maxY)            {                ballPos.Y = maxY;                ballSpeed.Y *= -1;            }            Rectangle paddle1Rect = new Rectangle((int)paddle1Pos.X, (int)paddle1Pos.Y, paddle.Width, paddle.Height);            Rectangle ballRect = new Rectangle((int)ballPos.X, (int)ballPos.Y, ball.Width, ball.Height);            if (ballRect.Intersects(paddle1Rect))            {                ballSpeed *= -1;            }            base.Update(gameTime);        }        /// <summary>        /// This is called when the game should draw itself.        /// </summary>        /// <param name="gameTime">Provides a snapshot of timing values.</param>        protected override void Draw(GameTime gameTime)        {            GraphicsDevice.Clear(Color.White);            // TODO: Add your drawing code here            spriteBatch.Begin();            spriteBatch.Draw(paddle, paddle1Pos, Color.White);            spriteBatch.Draw(ball, ballPos, Color.White);            spriteBatch.End();            base.Draw(gameTime);        }    }}[/source]

I've tried both allegro and sdl for a week each. I cant find many advanced allegro tutorials and I eventually want to move onto 3-d programming. What I really want is to be able to find a library that I can stick with til the end, no matter how hard or easy it is to learn.
Does anyone have suggestions on what I can use?

I'm using allegro with microsoft visual 2010 and used this tutorial to set up allegro for the compiler

blog.hamidnazari.com/2010/07/21/installing-allegro-on-visual-cpp-express-2010/

[source lang="cpp"]#include "stdafx.h"#include <allegro.h> int main(){ allegro_init(); install_keyboard(); set_gfx_mode(GFX_AUTODETECT_WINDOWED, 640, 480, 0, 0); triangle(screen, 320, 40, 147, 340, 493, 340, makecol(255, 0, 0)); circlefill(screen, 320, 240, 100, makecol(255, 255, 255)); return 0;} END_OF_MAIN();[/source]

when i compile this i get this error

1>------ Build started: Project: allegro, Configuration: Debug Win32 ------
1>  allegro.cpp
1>MSVCRTD.lib(crtexe.obj) : error LNK2019: unresolved external symbol _main referenced in function ___tmainCRTStartup
1>c:\documents\visual studio 2010\Projects\allegro\Debug\allegro.exe : fatal error LNK1120: 1 unresolved externals
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

im completely new to this compiler so i have no idea what i did wrong

well its really an oval lol. so id have to put that in a for loop in order to get each coordinates of each ball getting created every 3 seconds?

this is what i have for creating balls

[source lang="java"]class Ball    {        int x;        int y;        int width;        int height;                   public Ball(int x, int y, int width, int height)        {                     this.x = x;             this.y = y;             this.width = width;             this.height = height;        }//end ball        public void paint(Graphics g)        {                g.setColor(color[getRandomColor()]);                g.fillOval(x, y, width, height);        }                    //end paint    }                    //ball class[/source]

[source lang="java"] public void paint(Graphics g)    {            g.drawString("time: " + t, 20, 20);        for (Ball ball : BALLS)        {            ball.paint(g);        }                updateGame();    }[/source]
and this works fine for what i want. but im wondering how to grab these points from the arraylist and the use those points in the getBounds() method for collision against another ball

ok so i have random balls created every 3 seconds at random points x and y. I know these are stored in the array list, but how would i call the points from the list and then set the boundaries within the public Rectangle getBounds() method?

i changed the balls to rectangles to make it a little easier

the main rectangle has the coords 100, 100 and is 10, 10 high and wide, but the others are created by a random point so i dont have a set point to test the bounds againsst

I have 4 ovals being drawn to the screen and i need a way to check if a movable ball collides with the 4 that were drawn on the screen.
They 4 are drawn at random points on the screen but itd be near impossible to hit the exact center of the oval.
How would i detect a collision with the edges of the oval?

say i have the main ball moving right with starting coordinates 100, 100 and it comes into contact with a ball at 200, 100. Do i use a formula to measure this?

I figured it would be easier to switch from c# to c++ than from java to c++