问题
I'm trying to develop a game using OpenGL through LWJGL and Slick-Util (still not fully sure how they all relate to each other). I've figured out how to get the TrueTypeFonts to work . The problem is, that as soon as I got the fonts to work, the other aspects of my game (loading bar and map) don't display now at all. Any idea what the problem is? Here is the class for my game.
package manager;
import java.awt.Font;
import java.io.InputStream;
import org.lwjgl.LWJGLException;
import org.lwjgl.input.Keyboard;
import org.lwjgl.input.Mouse;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL11;
import org.newdawn.slick.Color;
import org.newdawn.slick.TrueTypeFont;
import org.newdawn.slick.UnicodeFont;
import org.newdawn.slick.util.ResourceLoader;
public class Game {
//Scene States0
public static final int STARTLOADING_SCENE = 0;
public static final int MAINMENU_SCENE = 1;
public static final int GAME_SCENE = 2;
int gameScene;
int loadingBarWidth;
int width, height;
int mouseXonMap,mouseYonMap;
String tileTypeHighlighted;
boolean mouseOnMap;
boolean wKeyDown, aKeyDown, sKeyDown, dKeyDown;
GameMap gameMap;
int mapOffsetX, mapOffsetY;
int tileWidth;
TrueTypeFont commonGameFont;
TrueTypeFont backupFont;
/**
* Runs initialization components
*/
public void start()
{
width = 640;
height = 480;
initGL(width,height);
init();
gameScene = 0;
gameMap = new GameMap(10,10);
mapOffsetX = 50;
mapOffsetY = 50;
tileWidth = 25;
while(true) {
GL11.glClear(GL11.GL_COLOR_BUFFER_BIT);
checkForInput();
updateObjects();
render();
Display.update();
Display.sync(100);
if(Display.isCloseRequested())
{
Display.destroy();
System.exit(0);
}
}
}
/**
* Initializes the display screen
* @param width - Width of the display
* @param height - Height of the display
*/
public void initGL(int width, int height)
{
try{
Display.setDisplayMode(new DisplayMode(width, height));
Display.create();
Display.setVSyncEnabled(true);
}
catch (LWJGLException e)
{
e.printStackTrace();
System.exit(0);
}
//Begin stuff from tutorial
GL11.glEnable(GL11.GL_TEXTURE_2D);
GL11.glShadeModel(GL11.GL_SMOOTH);
GL11.glDisable(GL11.GL_DEPTH_TEST);
GL11.glDisable(GL11.GL_LIGHTING);
GL11.glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
GL11.glClearDepth(1);
GL11.glEnable(GL11.GL_BLEND); //This line is important, but I don't know why.
GL11.glBlendFunc(GL11.GL_SRC_ALPHA, GL11.GL_ONE_MINUS_SRC_ALPHA);
GL11.glViewport(0,0,width,height);
GL11.glMatrixMode(GL11.GL_MODELVIEW);
GL11.glMatrixMode(GL11.GL_PROJECTION);
GL11.glLoadIdentity();
GL11.glOrtho(0, width, height, 0, 1, -1);
GL11.glMatrixMode(GL11.GL_MODELVIEW);
//End Stuff from tutorial
}
/**
* Initializes resources
*/
public void init()
{
//Initialize Resources
try {
InputStream inputStream = ResourceLoader.getResourceAsStream("res/8-Bit-Madness.ttf"); //The ResourceLoader.resourceExists() method says this .ttf exists.
if(ResourceLoader.resourceExists("res/8-Bit-Madness.ttf"))
{
System.out.println("Text Exists");
}
else
{
System.out.println("Text load error");
}
Font awtFont = Font.createFont(Font.TRUETYPE_FONT, inputStream);
awtFont = awtFont.deriveFont(36f); // set font size
commonGameFont = new TrueTypeFont(awtFont,false);
} catch (Exception e) {
e.printStackTrace();
}
}
public void checkForInput()
{
int mouseXonScreen = Mouse.getX();
int mouseYonScreen = Mouse.getY();
while (Keyboard.next()) {
if (Keyboard.getEventKeyState()) {
if (Keyboard.getEventKey() == Keyboard.KEY_W) {
System.out.println("W Key Pressed");
wKeyDown = true;
}
if (Keyboard.getEventKey() == Keyboard.KEY_A) {
System.out.println("A Key Pressed");
aKeyDown = true;
}
if (Keyboard.getEventKey() == Keyboard.KEY_S) {
System.out.println("S Key Pressed");
sKeyDown = true;
}
if (Keyboard.getEventKey() == Keyboard.KEY_D) {
System.out.println("D Key Pressed");
dKeyDown = true;
}
}
else
{
if (Keyboard.getEventKey() == Keyboard.KEY_W) {
System.out.println("W Key Released");
wKeyDown = false;
}
if (Keyboard.getEventKey() == Keyboard.KEY_A) {
System.out.println("A Key Released");
aKeyDown = false;
}
if (Keyboard.getEventKey() == Keyboard.KEY_S) {
System.out.println("S Key Released");
sKeyDown = false;
}
if (Keyboard.getEventKey() == Keyboard.KEY_D) {
System.out.println("D Key Released");
dKeyDown = false;
}
}
}
if(gameScene == GAME_SCENE)
{
if(mouseXonScreen>mapOffsetX && mouseXonScreen<mapOffsetX+(tileWidth*gameMap.getWidth()))
{
if(mouseYonScreen>mapOffsetY && mouseYonScreen<mapOffsetY+(tileWidth*gameMap.getHeight()))
{
mouseXonMap = (mouseXonScreen-mapOffsetX)/tileWidth;
mouseYonMap = (mouseYonScreen-mapOffsetY)/tileWidth;
tileTypeHighlighted = gameMap.getTileAt(mouseXonMap, mouseYonMap).getTileType();
mouseOnMap = true;
}
else
{
mouseOnMap = false;
}
}
else
{
mouseOnMap = false;
}
}
}
public void updateObjects()
{
if (gameScene == 0)
{
if (loadingBarWidth <= (width/2))
{
loadingBarWidth++;
}
else
{
gameScene = 2;
}
}
}
public void render()
{
if (gameScene == 0)
{
//These quads load properly, unless the blend line is in the program.
GL11.glColor3f(0.5f,0.5f,0.5f);
GL11.glBegin(GL11.GL_QUADS);
GL11.glVertex2f((width/4),(height/4));
GL11.glVertex2f((width/4),(height/4)+25);
GL11.glVertex2f((width/4)*3,(height/4)+25);
GL11.glVertex2f((width/4)*3,(height/4));
GL11.glEnd();
GL11.glColor3d(255d,255d,0d);
GL11.glBegin(GL11.GL_QUADS);
GL11.glVertex2f((width/4),(height/4));
GL11.glVertex2f((width/4),(height/4)+25);
GL11.glVertex2f((width/4)+loadingBarWidth,(height/4)+25);
GL11.glVertex2f((width/4)+loadingBarWidth,(height/4));
GL11.glEnd();
}
else if (gameScene == 2)
{
for(int x = 0; x<gameMap.getWidth(); x++)
{
for(int y = 0; y<gameMap.getHeight();y++)
{
//These quads load correctly, unless that blend line above is active.
GL11.glColor3d(gameMap.getTileAt(x,y).getRColor(), gameMap.getTileAt(x,y).getGColor(), gameMap.getTileAt(x,y).getBColor());
GL11.glBegin(GL11.GL_QUADS);
GL11.glVertex2f(mapOffsetX+(x*tileWidth), mapOffsetY+(y*tileWidth)+tileWidth);
GL11.glVertex2f(mapOffsetX+(x*tileWidth), mapOffsetY+(y*tileWidth));
GL11.glVertex2f(mapOffsetX+(x*tileWidth)+tileWidth, mapOffsetY+(y*tileWidth));
GL11.glVertex2f(mapOffsetX+(x*tileWidth)+tileWidth, mapOffsetY+(y*tileWidth)+tileWidth);
GL11.glEnd();
}
}
if(mouseOnMap)
{
commonGameFont.drawString(10,45, tileTypeHighlighted+ " Tile at X: "+ mouseXonMap +" Y: "+ mouseYonMap, Color.darkGray);
commonGameFont.drawString(10,20, "This is a long space to test sizing ... ... ... ... ... ... ...",Color.white);
}
}
}
public static void main(String[] args) {
Game game = new Game();
game.start();
}
}
回答1:
Not calling glEnable(GL_BLEND) in initGL but calling glEnable(GL_BLEND) when you draw the text should make it work. Example using your code:
if(mouseOnMap)
{
glEnable(GL_BLEND);
commonGameFont.drawString(10,20, "This is a long space to test sizing ... ... ... ... ... ... ...",Color.white);
commonGameFont.drawString(10,45, tileTypeHighlighted+ " Tile at X: "+ mouseXonMap +" Y: "+ mouseYonMap, Color.darkGray);
glDisable(GL_BLEND);
}
来源：https://stackoverflow.com/questions/26553916/opengl-lwjglslick-util-text-doesnt-display-properly