rendering texture(bypassing texture atlas for now)

Test.java

@@ -6,14 +6,19 @@ public class Test {
 		var window = engine.openWindow(1280, 720, "Skunkworks");
 		var img = engine.loadImage("C:\\Users\\dani\\Videos\\Screenshot 2022-06-25 17-00-59.png");
 		//var img = engine.loadImage("C:\\art\\kyoko.png");
+		var tex = window.loadTexture("C:\\Users\\dani\\Videos\\Screenshot 2022-06-25 17-00-59.png");
 		System.out.println(img.getPixel(new Vec2i(60, 60)));
 
 		while(!window.shouldClose()) {
 			window.tick();
 			var renderContext = window.renderStart();
-			renderContext.drawRectangle(
+			//renderContext.drawRectangle(
+			//	new Recti(100, 100, 100, 100),
+			//	new Color(150, 200, 250)
+			//);
+			renderContext.drawTextureRectangle(
 				new Recti(100, 100, 100, 100),
-				new Color(150, 200, 250)
+				tex
 			);
 			window.renderFinish(renderContext);
 		}

com/danitheskunk/skunkworks/Color.java

@@ -2,6 +2,7 @@ package com.danitheskunk.skunkworks;
 
 public final class Color {
 	final int r, g, b, a;
+	public final static Color WHITE = new Color(255, 255, 255);
 
 	public Color(int r, int g, int b) {
 		this.r = r;

com/danitheskunk/skunkworks/Engine.java

@@ -40,7 +40,7 @@ public class Engine {
 
 	public IWindow openWindow(int width, int height, String title) {
 		return switch(graphicsBackend) {
-			case OPENGL -> new GLWindow(width, height, title);
+			case OPENGL -> new GLWindow(width, height, title, this);
 		};
 	}
 }

com/danitheskunk/skunkworks/GLRenderContext.java

@@ -10,6 +10,8 @@ public class GLRenderContext implements IRenderContext{
 		var bl = rect.getBottomLeft();
 		var br = rect.getBottomRight();
 
+		//todo: make work with enabled textures
+
 		glColor4f(
 			color.getR() / 255.0f,
 			color.getG() / 255.0f,
@@ -26,4 +28,39 @@ public class GLRenderContext implements IRenderContext{
 		glVertex2i(bl.getX(), bl.getY());
 		glVertex2i(br.getX(), bl.getY());
 	}
+
+	@Override
+	public void drawTextureRectangle(Recti rect, ITexture texture) {
+		drawTextureRectangle(rect, texture, Color.WHITE);
+	}
+
+	@Override
+	public void drawTextureRectangle(Recti rect, ITexture texture, Color color) {
+		var tl = rect.getTopLeft();
+		var tr = rect.getTopRight();
+		var bl = rect.getBottomLeft();
+		var br = rect.getBottomRight();
+
+		glColor4f(
+			color.getR() / 255.0f,
+			color.getG() / 255.0f,
+			color.getB() / 255.0f,
+			color.getA() / 255.0f
+		);
+
+		//counter clockwise triangles
+		glTexCoord2f(0.0f, 1.0f);
+		glVertex2i(bl.getX(), bl.getY());
+		glTexCoord2f(1.0f, 0.0f);
+		glVertex2i(tr.getX(), tr.getY());
+		glTexCoord2f(0.0f, 0.0f);
+		glVertex2i(tl.getX(), tl.getY());
+
+		glTexCoord2f(1.0f, 0.0f);
+		glVertex2i(tr.getX(), tr.getY());
+		glTexCoord2f(0.0f, 1.0f);
+		glVertex2i(bl.getX(), bl.getY());
+		glTexCoord2f(1.0f, 1.0f);
+		glVertex2i(br.getX(), bl.getY());
+	}
 }

com/danitheskunk/skunkworks/GLTexture.java

@@ -0,0 +1,14 @@
+package com.danitheskunk.skunkworks;
+
+public class GLTexture implements ITexture {
+	private Recti texArea;
+
+	GLTexture(Recti texArea) {
+		this.texArea = texArea;
+	}
+
+	//setters
+	void setTexArea(Recti texArea) {
+		this.texArea = texArea;
+	}
+}

com/danitheskunk/skunkworks/GLTextureAtlas.java

@@ -0,0 +1,53 @@
+package com.danitheskunk.skunkworks;
+
+import org.lwjgl.BufferUtils;
+
+import java.nio.ByteBuffer;
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.lwjgl.opengl.GL11.*;
+
+class GLTextureAtlas {
+	private Image img;
+	private int textureID;
+	private List<GLTexture> textures;
+
+	GLTextureAtlas() {
+		img = new Image(new Vec2i(32, 32));
+		textureID = glGenTextures();
+		textures = new ArrayList<>();
+
+		glBindTexture(GL_TEXTURE_2D, textureID);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+
+	}
+
+	ITexture addTexture(Image img) {
+		//todo: do the actual texture stuff
+		this.img = img;
+		update();
+		var texture = new GLTexture(new Recti(new Vec2i(0, 0), img.getSize()));
+		textures.add(texture);
+		return texture;
+	}
+
+	void update() {
+		var buf = BufferUtils.createByteBuffer(img.getData().length);
+		buf.put(img.getData());
+		buf.flip();
+
+		glTexImage2D(
+			GL_TEXTURE_2D,
+			0,
+			GL_RGBA,
+			img.getWidth(),
+			img.getHeight(),
+			0,
+			GL_RGBA,
+			GL_UNSIGNED_BYTE,
+			buf
+		);
+	}
+}

com/danitheskunk/skunkworks/GLWindow.java

@@ -10,16 +10,20 @@ import static org.lwjgl.opengl.GL11.*;
 import static org.lwjgl.system.MemoryUtil.NULL;
 
 public class GLWindow implements IWindow {
+	private Engine engine;
 	private GLRenderContext renderContext;
 	private boolean shouldClose;
+	private GLTextureAtlas textureAtlas;
 	private long window;
 
-	public GLWindow(int width, int height, String title) {
+	public GLWindow(int width, int height, String title, Engine engine) {
 		GLFWErrorCallback.createPrint(System.err).set();
 		if(!glfwInit()) throw new IllegalStateException("Unable to initialize GLFW");
 
 		glfwDefaultWindowHints();
 
+		this.engine = engine;
+
 		window = glfwCreateWindow(width, height, title, NULL, NULL);
 		if(window == NULL) throw new RuntimeException("Failed to create GLFW window");
 
@@ -32,8 +36,10 @@ public class GLWindow implements IWindow {
 		glLoadIdentity();
 		glOrtho(0.0f, width, height, 0.0f, 0.0f, 1.0f);
 		glEnable(GL_COLOR);
+		glEnable(GL_TEXTURE_2D);
 
 		renderContext = new GLRenderContext();
+		textureAtlas = new GLTextureAtlas();
 
 		shouldClose = false;
 
@@ -42,6 +48,12 @@ public class GLWindow implements IWindow {
 		System.out.println(GL11.glGetInteger(GL_MAX_TEXTURE_SIZE));
 	}
 
+	@Override
+	public ITexture loadTexture(String path) {
+		var img = engine.loadImage(path);
+		return textureAtlas.addTexture(img);
+	}
+
 	@Override
 	public void renderFinish(IRenderContext context) {
 		glEnd();

com/danitheskunk/skunkworks/IRenderContext.java

@@ -2,4 +2,6 @@ package com.danitheskunk.skunkworks;
 
 public interface IRenderContext {
 	void drawRectangle(Recti rect, Color color);
+	void drawTextureRectangle(Recti rect, ITexture texture);
+	void drawTextureRectangle(Recti rect, ITexture texture, Color color);
 }

com/danitheskunk/skunkworks/ITexture.java

@@ -0,0 +1,5 @@
+package com.danitheskunk.skunkworks;
+
+public interface ITexture {
+
+}

com/danitheskunk/skunkworks/IWindow.java

@@ -1,6 +1,7 @@
 package com.danitheskunk.skunkworks;
 
 public interface IWindow {
+	ITexture loadTexture(String path);
 	void renderFinish(IRenderContext context);
 	IRenderContext renderStart();
 	boolean shouldClose();

com/danitheskunk/skunkworks/Image.java

@@ -28,8 +28,20 @@ public class Image {
 		return data;
 	}
 
+	public Vec2i getSize() {
+		return size;
+	}
+
+	public int getWidth() {
+		return size.getX();
+	}
+
+	public int getHeight() {
+		return size.getY();
+	}
+
 	public Color getPixel(Vec2i pos) {
-		int i = pos.getX() * 4 + pos.getY() * 4 * width;
+		int i = pos.getX() * 4 + pos.getY() * 4 * size.getX();
 		return new Color(
 			((int)data[i + 0]) & 0xFF,
 			((int)data[i + 1]) & 0xFF,
@@ -39,7 +51,7 @@ public class Image {
 	}
 
 	public void setPixel(Vec2i pos, Color col) {
-		int i = pos.getX() * 4 + pos.getY() * 4 * width;
+		int i = pos.getX() * 4 + pos.getY() * 4 * size.getX();
 		data[i + 0] = (byte)(col.r & 0xFF);
 		data[i + 1] = (byte)(col.g & 0xFF);
 		data[i + 2] = (byte)(col.b & 0xFF);