Drawing independent Triangles in libgdx - libgdx

Question

How can I draw Triangles that are independent from each other? I wat to make a ship game and when the ship collides with the triangle I want it to disapear. But I can't find a good way to do this. Creating Mesh isn't the best solution because they end hardcoded, Using a shaperenderer doesn't seems to be good either because I can't control them separately. So I'm stuck, anyone has any idea?

Answer 1

I ended up solving my problem this way:
I created a object Triangle that created a Mesh. In that object I had another problem, the bind wasn't working, but I figured out how to solve it, I'm not sure how I solved it, but it works. Here's the final code that worked for me:
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.Mesh;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.VertexAttribute;
import com.badlogic.gdx.graphics.VertexAttributes.Usage;
import com.badlogic.gdx.graphics.glutils.ShaderProgram;
public class Triangle {
ShaderProgram shader;
Mesh mesh;
Texture texture;
float[] attributes = new float[15];
static int screenWidth;
static int screenHeight;
public Triangle(float[] vertices, float[] color, float[] textureVertices, Texture texture){
this.texture = texture;
createShader();
int j = 0;
int k = 0;
int l = 0;
if ((screenWidth <= 0) || (screenHeight <= 0))
{
throw new NullPointerException("Invalid screen dimensions for triangles.");
}
for (int i = 0; i < vertices.length; i++) {
vertices[i] = (vertices[i]/screenWidth - 1); // (vertices[i] - width/2)/(width/2)
vertices[++i] = (vertices[i]/screenHeight - 1); // (vertices[i] - height/2)/(height/2)
}
for (int i = 0; i < attributes.length;) {
attributes[i++] = vertices[j++];
attributes[i++] = vertices[j++];
attributes[i++] = color[k++];
attributes[i++] = textureVertices[l++];
attributes[i++] = textureVertices[l++];
}
mesh = new Mesh(false, attributes.length, 0, new VertexAttribute(
Usage.Position, 2, "a_position"), new VertexAttribute(
Usage.ColorPacked, 4, "a_color"), new VertexAttribute(
Usage.TextureCoordinates, 2, "a_texCoords"));
mesh.setVertices(attributes);
}
public static void setDimensions(int paramWidth, int paramHeight)
{
screenWidth = paramWidth;
screenHeight = paramHeight;
}
public void createShader()
{
// this shader tells opengl where to put things
String vertexShader = "attribute vec4 a_position; \n"
+ "attribute vec4 a_color; \n"
+ "attribute vec2 a_texCoords; \n"
+ "varying vec4 v_color; \n"
+ "varying vec2 v_texCoords; \n"
+ "void main() \n"
+ "{ \n"
+ " v_color = a_color; \n"
+ " v_texCoords = a_texCoords; \n"
+ " gl_Position = a_position; \n"
+ "} \n";
// this one tells it what goes in between the points (i.e
// colour/texture)
String fragmentShader = "#ifdef GL_ES \n"
+ "precision mediump float; \n"
+ "#endif \n"
+ "varying vec4 v_color; \n"
+ "varying vec2 v_texCoords; \n"
+ "uniform sampler2D u_texture;\n"
+ "void main() \n"
+ "{ \n"
+ " gl_FragColor = v_color * texture2D(u_texture, v_texCoords); \n"
+ "} \n";
shader = new ShaderProgram(vertexShader, fragmentShader);
}
public void render() {
Gdx.gl20.glViewport(0, 0, Gdx.graphics.getWidth(),
Gdx.graphics.getHeight());
Gdx.gl20.glEnable(GL20.GL_TEXTURE_2D);
Gdx.gl20.glActiveTexture(GL20.GL_TEXTURE);
shader.begin();
texture.bind(0);
shader.setUniformi("u_texture", 0);
mesh.render(shader, GL20.GL_TRIANGLES);
shader.end();
}
public void dispose() {
texture.dispose();
mesh.dispose();
shader.dispose();
}
}
I hope it helps someone!