Add support for textures

.gitignore

@@ -132,4 +132,7 @@ gradle-app.setting
 ### Gradle Patch ###
 **/build/
 
+### Textures and other resources ###
+*.png
+
 # End of https://www.toptal.com/developers/gitignore/api/java,gradle,intellij

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/object/material/Material.java

@@ -1,13 +1,16 @@
 package com.bartlomiejpluta.samplegame.core.gl.object.material;
 
+import com.bartlomiejpluta.samplegame.core.gl.object.texture.Texture;
 import lombok.Getter;
 import org.joml.Vector4f;
 
 @Getter
 public class Material {
    private final Vector4f color = new Vector4f();
+   private final Texture texture;
 
-   private Material(float r, float g, float b, float alpha) {
+   private Material(Texture texture, float r, float g, float b, float alpha) {
+      this.texture = texture;
       setColor(r, g, b, alpha);
    }
 
@@ -18,7 +21,29 @@ public class Material {
       color.w = alpha;
    }
 
+   public boolean hasTexture() {
+      return texture != null;
+   }
+
+   public void activateTextureIfExists() {
+      if(hasTexture()) {
+         texture.activate();
+      }
+   }
+
    public static Material colored(float r, float g, float b, float alpha) {
-      return new Material(r, g, b, alpha);
+      return new Material(null, r, g, b, alpha);
+   }
+
+   public static Material textured(Texture texture) {
+      return new Material(texture, 1, 1, 1, 1);
+   }
+
+   public static Material textured(Texture texture, float r, float g, float b, float alpha) {
+      return new Material(texture, r, g, b, alpha);
+   }
+
+   public static Material textured(Texture texture, float alpha) {
+      return new Material(texture, 1, 1, 1, alpha);
    }
 }

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/object/mesh/Mesh.java

@@ -26,12 +26,14 @@ public class Mesh implements Renderable {
    @Setter
    private Material material;
 
-   public Mesh(float[] vertices, int[] elements) {
+   public Mesh(float[] vertices, float[] texCoords, int[] elements) {
       try(var stack = MemoryStack.stackPush()) {
          elementsCount = elements.length;
          var verticesBuffer = stack.mallocFloat(vertices.length);
+         var texCoordsBuffer = stack.mallocFloat(texCoords.length);
          var elementsBuffer = stack.mallocInt(elementsCount);
          verticesBuffer.put(vertices).flip();
+         texCoordsBuffer.put(texCoords).flip();
          elementsBuffer.put(elements).flip();
 
          vaoId = glGenVertexArrays();
@@ -41,7 +43,13 @@ public class Mesh implements Renderable {
          vboIds.add(vboId);
          glBindBuffer(GL_ARRAY_BUFFER, vboId);
          glBufferData(GL_ARRAY_BUFFER, verticesBuffer, GL_STATIC_DRAW);
-         glVertexAttribPointer(0, 3, GL_FLOAT, false, 0, 0);
+         glVertexAttribPointer(0, 2, GL_FLOAT, false, 0, 0);
+
+         vboId = glGenBuffers();
+         vboIds.add(vboId);
+         glBindBuffer(GL_ARRAY_BUFFER, vboId);
+         glBufferData(GL_ARRAY_BUFFER, texCoordsBuffer, GL_STATIC_DRAW);
+         glVertexAttribPointer(1, 2, GL_FLOAT, false, 0, 0);
 
          vboId = glGenBuffers();
          vboIds.add(vboId);
@@ -57,8 +65,10 @@ public class Mesh implements Renderable {
    public void render(Window window, ShaderManager shaderManager) {
       glBindVertexArray(vaoId);
       glEnableVertexAttribArray(0);
+      glEnableVertexAttribArray(1);
       glDrawElements(GL_TRIANGLES, elementsCount, GL_UNSIGNED_INT, 0);
       glDisableVertexAttribArray(0);
+      glDisableVertexAttribArray(1);
       glBindVertexArray(0);
    }
 

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/object/texture/DefaultTextureManager.java

@@ -0,0 +1,29 @@
+package com.bartlomiejpluta.samplegame.core.gl.object.texture;
+
+import com.bartlomiejpluta.samplegame.core.util.res.ResourcesManager;
+import lombok.RequiredArgsConstructor;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
+
+import java.util.HashMap;
+import java.util.Map;
+
+@Component
+@RequiredArgsConstructor(onConstructor = @__(@Autowired))
+public class DefaultTextureManager implements TextureManager {
+   private final ResourcesManager resourcesManager;
+   private final Map<String, Texture> loadedTextures = new HashMap<>();
+
+   @Override
+   public Texture loadTexture(String textureFileName) {
+      var texture = loadedTextures.get(textureFileName);
+      if(texture != null) {
+         return texture;
+      }
+
+      var buffer = resourcesManager.loadResourceAsByteBuffer(textureFileName);
+      texture = new Texture(textureFileName, buffer);
+      loadedTextures.put(textureFileName, texture);
+      return texture;
+   }
+}

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/object/texture/Texture.java

@@ -0,0 +1,53 @@
+package com.bartlomiejpluta.samplegame.core.gl.object.texture;
+
+import com.bartlomiejpluta.samplegame.core.error.AppException;
+import org.lwjgl.BufferUtils;
+import org.lwjgl.system.MemoryStack;
+import org.lwjgl.system.MemoryUtil;
+
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
+import java.nio.channels.FileChannel;
+
+import static org.lwjgl.opengl.GL11.*;
+import static org.lwjgl.opengl.GL13.GL_TEXTURE0;
+import static org.lwjgl.opengl.GL13.glActiveTexture;
+import static org.lwjgl.opengl.GL30.glGenerateMipmap;
+import static org.lwjgl.stb.STBImage.*;
+
+public class Texture {
+   private static final int DESIRED_CHANNELS = 4;
+
+   private final int textureId;
+   private final int width;
+   private final int height;
+
+   Texture(String textureFilename, ByteBuffer buffer) {
+      try (var stack = MemoryStack.stackPush()) {
+         var widthBuffer = stack.mallocInt(1);
+         var heightBuffer = stack.mallocInt(1);
+         var channelsBuffer = stack.mallocInt(1);
+
+         buffer = stbi_load_from_memory(buffer, widthBuffer, heightBuffer, channelsBuffer, DESIRED_CHANNELS);
+         if (buffer == null) {
+            throw new AppException("Image file [%s] could not be loaded: %s", textureFilename, stbi_failure_reason());
+         }
+
+         width = widthBuffer.get();
+         height = heightBuffer.get();
+
+         textureId = glGenTextures();
+
+         glBindTexture(GL_TEXTURE_2D, textureId);
+         glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+         glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, buffer);
+         glGenerateMipmap(GL_TEXTURE_2D);
+      }
+   }
+
+   public void activate() {
+      glActiveTexture(GL_TEXTURE0);
+      glBindTexture(GL_TEXTURE_2D, textureId);
+   }
+}

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/object/texture/TextureManager.java

@@ -0,0 +1,5 @@
+package com.bartlomiejpluta.samplegame.core.gl.object.texture;
+
+public interface TextureManager {
+   Texture loadTexture(String textureFileName);
+}

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/render/DefaultRenderer.java

@@ -25,7 +25,9 @@ public class DefaultRenderer implements Renderer {
               .createUniform(UniformName.UNI_MODEL_MATRIX)
               .createUniform(UniformName.UNI_VIEW_MATRIX)
               .createUniform(UniformName.UNI_PROJECTION_MATRIX)
-              .createUniform(UniformName.UNI_OBJECT_COLOR);
+              .createUniform(UniformName.UNI_OBJECT_COLOR)
+              .createUniform(UniformName.UNI_HAS_OBJECT_TEXTURE)
+              .createUniform(UniformName.UNI_TEXTURE_SAMPLER);
    }
 
    @Override
@@ -45,7 +47,7 @@ public class DefaultRenderer implements Renderer {
    }
 
    private void updateViewport(Window window) {
-      if(window.isResized()) {
+      if (window.isResized()) {
          glViewport(0, 0, window.getWidth(), window.getHeight());
          window.setResized(false);
       }

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/shader/constant/UniformName.java

@@ -5,4 +5,6 @@ public interface UniformName {
    String UNI_VIEW_MATRIX = "viewMatrix";
    String UNI_PROJECTION_MATRIX = "projectionMatrix";
    String UNI_OBJECT_COLOR = "objectColor";
+   String UNI_HAS_OBJECT_TEXTURE = "hasTexture";
+   String UNI_TEXTURE_SAMPLER = "sampler";
 }

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/shader/manager/DefaultShaderManager.java

@@ -83,6 +83,12 @@ public class DefaultShaderManager implements ShaderManager {
       return this;
    }
 
+   @Override
+   public ShaderManager setUniform(String uniformName, boolean value) {
+      current.setUniform(uniformName, value);
+      return this;
+   }
+
    @Override
    public ShaderManager setUniform(String uniformName, float value) {
       current.setUniform(uniformName, value);

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/shader/manager/ShaderManager.java

@@ -17,40 +17,30 @@ public interface ShaderManager {
 
    ShaderManager createUniform(String uniformName);
 
-
    ShaderManager createUniform(String uniformName, Uniform uniform);
 
-
    ShaderManager createUniforms(String uniformName, int size);
 
-
    ShaderManager createUniforms(String uniformName, int size, Uniform uniform);
 
-
    ShaderManager setUniform(String uniformName, int value);
 
+   ShaderManager setUniform(String uniformName, boolean value);
 
    ShaderManager setUniform(String uniformName, float value);
 
-
    ShaderManager setUniform(String uniformName, Vector3f value);
 
-
    ShaderManager setUniform(String uniformName, Vector4f value);
 
-
    ShaderManager setUniform(String uniformName, Matrix3f value);
 
-
    ShaderManager setUniform(String uniformName, Matrix4f value);
 
-
    ShaderManager setUniform(String uniformName, Uniform uniform);
 
-
    ShaderManager setUniform(String uniformName, int index, Uniform uniform);
 
-
    ShaderManager setUniforms(String uniformName, Uniform[] uniforms);
 
    void cleanUp();

app/src/main/java/com/bartlomiejpluta/samplegame/core/gl/shader/program/ShaderProgram.java

@@ -103,6 +103,10 @@ public class ShaderProgram {
       glUniform1i(uniforms.get(uniformName), value);
    }
 
+   public void setUniform(String uniformName, boolean value) {
+      glUniform1i(uniforms.get(uniformName), value ? 1 : 0);
+   }
+
    public void setUniform(String uniformName, float value) {
       glUniform1f(uniforms.get(uniformName), value);
    }

app/src/main/java/com/bartlomiejpluta/samplegame/core/util/res/ResourcesManager.java

@@ -1,9 +1,13 @@
 package com.bartlomiejpluta.samplegame.core.util.res;
 
 import com.bartlomiejpluta.samplegame.core.error.AppException;
+import com.bartlomiejpluta.samplegame.core.gl.object.texture.Texture;
 import org.springframework.stereotype.Component;
 
+import java.io.IOException;
 import java.io.InputStream;
+import java.nio.ByteBuffer;
+import java.nio.ByteOrder;
 import java.util.Scanner;
 
 @Component
@@ -16,4 +20,17 @@ public class ResourcesManager {
          throw new AppException(e);
       }
    }
+
+   public ByteBuffer loadResourceAsByteBuffer(String fileName) {
+      try {
+         var bytes = Texture.class.getResourceAsStream(fileName).readAllBytes();
+         return ByteBuffer
+                 .allocateDirect(bytes.length)
+                 .order(ByteOrder.nativeOrder())
+                 .put(bytes)
+                 .flip();
+      } catch (IOException e) {
+         throw new AppException(e);
+      }
+   }
 }

app/src/main/java/com/bartlomiejpluta/samplegame/core/world/object/RenderableObject.java

@@ -21,6 +21,7 @@ public abstract class RenderableObject extends Object implements Renderable {
 
    @Override
    public void render(Window window, ShaderManager shaderManager) {
+      getMaterial().activateTextureIfExists();
       mesh.render(window, shaderManager);
    }
 

app/src/main/java/com/bartlomiejpluta/samplegame/core/world/scene/Scene.java

@@ -29,6 +29,9 @@ public class Scene implements Renderable {
       for(var object : objects) {
          shaderManager.setUniform(UniformName.UNI_MODEL_MATRIX, object.getModelMatrix());
          shaderManager.setUniform(UniformName.UNI_OBJECT_COLOR, object.getMaterial().getColor());
+         shaderManager.setUniform(UniformName.UNI_HAS_OBJECT_TEXTURE, object.getMaterial().hasTexture());
+         shaderManager.setUniform(UniformName.UNI_TEXTURE_SAMPLER, 0);
+
          object.render(window, shaderManager);
       }
    }

app/src/main/java/com/bartlomiejpluta/samplegame/game/logic/DefaultGameLogic.java

@@ -1,11 +1,13 @@
 package com.bartlomiejpluta.samplegame.game.logic;
 
 import com.bartlomiejpluta.samplegame.core.gl.object.material.Material;
+import com.bartlomiejpluta.samplegame.core.gl.object.texture.TextureManager;
 import com.bartlomiejpluta.samplegame.core.gl.render.Renderer;
 import com.bartlomiejpluta.samplegame.core.logic.GameLogic;
 import com.bartlomiejpluta.samplegame.core.ui.Window;
 import com.bartlomiejpluta.samplegame.core.world.camera.Camera;
 import com.bartlomiejpluta.samplegame.core.world.scene.Scene;
+import com.bartlomiejpluta.samplegame.game.object.Sprite;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -16,6 +18,8 @@ import org.springframework.stereotype.Component;
 @RequiredArgsConstructor(onConstructor = @__(@Autowired))
 public class DefaultGameLogic implements GameLogic {
    private final Renderer renderer;
+   private final TextureManager textureManager;
+
    private final Camera camera = new Camera();
    private final Scene scene = new Scene(camera);
 
@@ -24,7 +28,12 @@ public class DefaultGameLogic implements GameLogic {
       log.info("Initializing game logic");
       renderer.init();
 
-
+      var sprite = new Sprite(Material.textured(textureManager.loadTexture("/textures/grass.png")));
+      var sprite2 = new Sprite(Material.colored(0.7f, 1.0f, 0.4f, 1.0f));
+      sprite.setPosition(320, 240);
+      sprite2.setPosition(110, 110);
+      scene.add(sprite2);
+      scene.add(sprite);
    }
 
    @Override

app/src/main/java/com/bartlomiejpluta/samplegame/game/object/Sprite.java

@@ -0,0 +1,31 @@
+package com.bartlomiejpluta.samplegame.game.object;
+
+import com.bartlomiejpluta.samplegame.core.gl.object.material.Material;
+import com.bartlomiejpluta.samplegame.core.gl.object.mesh.Mesh;
+import com.bartlomiejpluta.samplegame.core.world.object.RenderableObject;
+
+public class Sprite extends RenderableObject {
+   private static final float[] VERTICES = new float[]{
+           -100, 100,
+           -100, -100,
+           100, -100,
+           100, 100
+   };
+
+   private static final float[] TEX_COORDS = new float[] {
+           0, 0,
+           0, 1,
+           1, 1,
+           1, 0
+   };
+
+   private static final int[] ELEMENTS = new int[]{
+           0, 1, 2,
+           2, 3, 0
+   };
+
+   public Sprite(Material material) {
+      super(new Mesh(VERTICES, TEX_COORDS, ELEMENTS));
+      setMaterial(material);
+   }
+}

app/src/main/resources/shaders/default.fs

@@ -1,10 +1,21 @@
 #version 330
 
 uniform vec4 objectColor;
+uniform int hasTexture;
+uniform sampler2D sampler;
+
+in vec2 fragmentTexCoord;
 
 out vec4 fragColor;
 
 void main()
 {
+   if(hasTexture == 1)
+   {
+      fragColor = objectColor * texture(sampler, fragmentTexCoord);
+   }
+   else
+   {
       fragColor = objectColor;
+   }
 }

app/src/main/resources/shaders/default.vs

@@ -4,9 +4,13 @@ uniform mat4 modelMatrix;
 uniform mat4 viewMatrix;
 uniform mat4 projectionMatrix;
 
-layout(location=0) in vec3 position;
+layout(location=0) in vec2 position;
+layout(location=1) in vec2 texCoord;
+
+out vec2 fragmentTexCoord;
 
 void main()
 {
-   gl_Position = projectionMatrix * viewMatrix * modelMatrix * vec4(position, 1.0);
+   gl_Position = projectionMatrix * viewMatrix * modelMatrix * vec4(position, 0.0, 1.0);
+   fragmentTexCoord = texCoord;
 }