When using shaders in 3D libgdx we encounter an issue of binding textures to models. Sometimes all environment and 3d models used in game use same textures , specially when you are working with multiple models.
Following codes is used in this example
Fragment Shader
In start of render
Following codes is used in this example
Vetex Shader
attribute vec3 a_position; attribute vec3 a_normal; attribute vec2 a_texCoord0; uniform mat4 u_worldTrans; uniform mat4 u_projTrans; varying vec2 v_texCoord0; void main()
{ v_texCoord0 = a_texCoord0;
gl_Position = u_projTrans * u_worldTrans * vec4(a_position, 1.0);
}
#ifdef GL_ES
precision mediump float; #endif
uniform vec3 u_colorU; uniform vec3 u_colorV; varying vec2 v_texCoord0; uniform sampler2D u_texture; void main() { gl_FragColor = texture2D(u_texture , v_texCoord0); }
In start of render
Gdx.gl.glViewport(0, 0, Gdx.graphics.getWidth(), Gdx.graphics.getHeight());
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT | GL20.GL_DEPTH_BUFFER_BIT);
// Gdx.gl20.glActiveTexture(GL20.GL_TEXTURE0);
// texture.bind();
Gdx.gl20.glEnable(GL20.GL_TEXTURE_2D);
Gdx.gl20.glEnable(GL20.GL_BLEND);
And here is Working multi texture binding with single shader
Happy coding :P. Please let me know in comments if this helps :D
import com.badlogic.gdx.Gdx;import com.badlogic.gdx.graphics.Camera;import com.badlogic.gdx.graphics.Color;import com.badlogic.gdx.graphics.GL20;import com.badlogic.gdx.graphics.GLTexture;import com.badlogic.gdx.graphics.g3d.Renderable;import com.badlogic.gdx.graphics.g3d.Shader;import com.badlogic.gdx.graphics.g3d.attributes.ColorAttribute;import com.badlogic.gdx.graphics.g3d.attributes.TextureAttribute;import com.badlogic.gdx.graphics.g3d.utils.RenderContext;import com.badlogic.gdx.graphics.glutils.ShaderProgram;import com.badlogic.gdx.utils.GdxRuntimeException; import screens.PlayScreen; public class TestShader implements Shader { ShaderProgram program; Camera camera; RenderContext context; int u_projTrans; int u_worldTrans; int u_colorU; int u_colorV; PlayScreen playScreen; public TestShader(PlayScreen playScreen) { this.playScreen = playScreen; } @Override public void init() { String vert = Gdx.files.internal("shaders/uvcolor.vertex.glsl").readString(); String frag = Gdx.files.internal("shaders/uvcolor.fragment.glsl").readString(); System.out.println("hello shader" + vert); program = new ShaderProgram(vert, frag); program.pedantic = false; if (!program.isCompiled()) throw new GdxRuntimeException(program.getLog()); u_projTrans = program.getUniformLocation("u_projTrans"); u_worldTrans = program.getUniformLocation("u_worldTrans"); u_colorU = program.getUniformLocation("u_colorU"); u_colorV = program.getUniformLocation("u_colorV"); } @Override public void dispose() { program.dispose(); } @Override public void begin(Camera camera, RenderContext context) { this.camera = camera; this.context = context; program.begin(); program.setUniformMatrix(u_projTrans, camera.combined); context.setDepthTest(GL20.GL_LEQUAL); context.setCullFace(GL20.GL_BACK); } @Override public void render(Renderable renderable) { program.setUniformMatrix(u_worldTrans, renderable.worldTransform); Color colorU = ((ColorAttribute)renderable.material.get(ColorAttribute.Diffuse)).color; Color colorV = ((ColorAttribute)renderable.material.get(ColorAttribute.Diffuse)).color; program.setUniformf(u_colorU, colorU.r, colorU.g, colorU.b); program.setUniformf(u_colorV, colorV.r, colorV.g, colorV.b); ((TextureAttribute)renderable.material.get(TextureAttribute.Diffuse)).textureDescription.texture.bind(); renderable.meshPart.render(program); } @Override public void end() { program.end(); } @Override public int compareTo(Shader other) { return 0; } @Override public boolean canRender(Renderable renderable) { return renderable.material.has(ColorAttribute.Diffuse); } }
Happy coding :P. Please let me know in comments if this helps :D
