From d69c8e3a5e131797ed3f761bfed321f375172994 Mon Sep 17 00:00:00 2001
From: zlago <104219492+zlago@users.noreply.github.com>
Date: Mon, 17 Nov 2025 20:56:24 +0100
Subject: [PATCH] a shallow game will never be good, it takes depth

---
 src/assets.c++ |  2 +-
 src/batch.c    | 19 ++++++++++---------
 src/batch.h    |  6 +++---
 src/main.c++   |  6 ++++--
 src/main.h++   |  2 +-
 src/spr2D.glsl |  4 ++--
 6 files changed, 21 insertions(+), 18 deletions(-)

diff --git a/src/assets.c++ b/src/assets.c++
index 904c9bd..32764f4 100644
--- a/src/assets.c++
+++ b/src/assets.c++
@@ -9,7 +9,7 @@
 #include "rect-pack.h"
 #include "batch.h"
 
-#include <glad/gles2.h>
+#include "glad/gles2.h"
 
 #include "main.h++"
 
diff --git a/src/batch.c b/src/batch.c
index 2c0d7c3..7e62e15 100644
--- a/src/batch.c
+++ b/src/batch.c
@@ -3,13 +3,14 @@
 #include <stdlib.h>
 #include <stdbool.h>
 #include <string.h>
-#include <glad/gles2.h>
+#include <stddef.h>
+#include "glad/gles2.h"
 
 #include "batch.h"
 
 struct batch {
-	struct vertices { // 8 bytes
-		int16_t x, y;  // 4 bytes
+	struct vertices { // 10 bytes
+		int16_t x, y, z;  // 6 bytes
 		uint16_t s, t; // 4 bytes
 		// must subtract 1 after multiplying
 	} (*vertices)[4];
@@ -38,17 +39,17 @@ struct batch {
 
 static void batch_insert(struct vertices v[4], GLuint texture);
 
-void batch_blit_flippable(int x, int y, struct texture *tex, struct crop *crop) {
+void batch_blit_flippable(int x, int y, int z, struct texture *tex, struct crop *crop) {
 	if (crop->w < 0) {
 		x -= crop->w;
 	}
 	if (crop->h < 0) {
 		y -= crop->h;
 	}
-	batch_blit(x, y, tex, crop);
+	batch_blit(x, y, z, tex, crop);
 }
 
-void batch_blit(int x, int y, struct texture *tex, struct crop *crop) {
+void batch_blit(int x, int y, int z, struct texture *tex, struct crop *crop) {
 	unsigned s1, s2, t1, t2;
 	if (tex->flipped) {
 		s1 = tex->x + crop->y;
@@ -63,7 +64,7 @@ void batch_blit(int x, int y, struct texture *tex, struct crop *crop) {
 	}
 
 	struct vertices vi = {
-		.x = x, .y = y,
+		.x = x, .y = y, .z = z,
 		.s = s1 * tex->size,
 		.t = t1 * tex->size,
 	};
@@ -126,8 +127,8 @@ void batch_flush(void) {
 
 	glUseProgram(batch.program);
 
-	glVertexAttribPointer(batch.aVertCoord, 2, GL_SHORT, GL_FALSE, sizeof (struct vertices), (void *) 0);
-	glVertexAttribPointer(batch.aTexCoord, 2, GL_UNSIGNED_SHORT, GL_TRUE, sizeof (struct vertices), (void *) 4);
+	glVertexAttribPointer(batch.aVertCoord, 3, GL_SHORT, GL_FALSE, sizeof (struct vertices), (void *) offsetof (struct vertices, x));
+	glVertexAttribPointer(batch.aTexCoord, 2, GL_UNSIGNED_SHORT, GL_TRUE, sizeof (struct vertices), (void *) offsetof (struct vertices, s));
 
 	glEnableVertexAttribArray(batch.aVertCoord);
 	glEnableVertexAttribArray(batch.aTexCoord);
diff --git a/src/batch.h b/src/batch.h
index 475fe42..1fcc44e 100644
--- a/src/batch.h
+++ b/src/batch.h
@@ -7,7 +7,7 @@ extern "C" {
 #include <limits.h>
 #include <stdint.h>
 #include <stdbool.h>
-#include <glad/gles2.h>
+#include "glad/gles2.h"
 
 struct texture {
 	GLuint texture;
@@ -21,8 +21,8 @@ struct crop {
 	int w, h;
 };
 
-void batch_blit(int x, int y, struct texture *tex, struct crop *crop);
-void batch_blit_flippable(int x, int y, struct texture *tex, struct crop *crop);
+void batch_blit(int x, int y, int z, struct texture *tex, struct crop *crop);
+void batch_blit_flippable(int x, int y, int z, struct texture *tex, struct crop *crop);
 
 void batch_flush(void);
 
diff --git a/src/main.c++ b/src/main.c++
index e7d1806..eb669a5 100644
--- a/src/main.c++
+++ b/src/main.c++
@@ -1,4 +1,4 @@
-#include <glad/gles2.h>
+#include "glad/gles2.h"
 #include <SDL3/SDL.h>
 #define SDL_MAIN_USE_CALLBACKS 1
 #include <SDL3/SDL_main.h>
@@ -157,9 +157,10 @@ SDL_AppResult SDL_AppIterate(void *) {
 	glViewport(0, 0, WINDOW_VIRTUAL, WINDOW_VIRTUAL);
 	glClearColor(0.0, 0.0, 0.0, 0.0);
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+	glEnable(GL_DEPTH_TEST);
 
 	struct crop c = {0, 0, 64, 64};
-	batch_blit(-32, -32, &textures.at("turret"), &c);
+	batch_blit(-32, -32, 0, &textures.at("turret"), &c);
 	batch_flush();
 
 	glBindFramebuffer(GL_FRAMEBUFFER, 0);
@@ -185,6 +186,7 @@ SDL_AppResult SDL_AppIterate(void *) {
 	}
 	glClearColor(0.0, 0.0, 0.0, 0.0);
 	glClear(GL_COLOR_BUFFER_BIT);
+	glDisable(GL_DEPTH_TEST);
 	
 	glBindBuffer(GL_ARRAY_BUFFER, fb.vbo);
 	glUseProgram(fb.program);
diff --git a/src/main.h++ b/src/main.h++
index dbfd4d0..fbc4862 100644
--- a/src/main.h++
+++ b/src/main.h++
@@ -1,6 +1,6 @@
 #pragma once
 
-#include <glad/gles2.h>
+#include "glad/gles2.h"
 #include <SDL3/SDL.h>
 
 #include <unordered_map>
diff --git a/src/spr2D.glsl b/src/spr2D.glsl
index 33dafcd..fa3176b 100644
--- a/src/spr2D.glsl
+++ b/src/spr2D.glsl
@@ -10,12 +10,12 @@ varying vec2 vTexCoord;
 
 %%
 
-attribute vec2 aVertCoord;
+attribute vec3 aVertCoord;
 attribute vec2 aTexCoord;
 
 void main(void) {
 	vTexCoord = aTexCoord;
-	gl_Position = vec4(aVertCoord * vec2(1.0 / 64.0), 0.0, 1.0);
+	gl_Position = vec4(aVertCoord * (1.0 / 64.0), 1.0);
 }
 
 ##