3 files changed, 78 insertions, 4 deletions
diff --git a/src/engine/draw_screen.c b/src/engine/draw_screen.c
new file mode 100644
index 0000000..acf5b41
--- /dev/null
+++ b/src/engine/draw_screen.c
@@ -0,0 +1,61 @@
+#include "draw_screen.h"
+
+uint8_t hh_world_to_tile(vec2 pos){
+	
+    FILE* level = fopen("../test/bin/test_map.bin", "rb"); /* open binary file */
+    if (!level) { /* check if file opened successfully */
+        fprintf(stderr, "Error: Failed to open file.\n");
+        return 0;
+    }
+	int index = (pos.y + pos.x);
+	fseek(level, (index * sizeof(int)) + sizeof(int), SEEK_SET);
+	int* tile = (int*)malloc(sizeof(int));
+   fread(tile, sizeof(int), 1, level); // read 1 tile from binary
+
+	fclose(level);
+	int val = *tile;
+	free(tile);
+	return val;
+}
+
+
+// remeber old value to know which part to update.
+vec2 previousViewport = { .x = 0, .y = 0 };
+void hh_draw_screen(vec_cor viewport){
+	if (viewport.x == previousViewport.x && viewport.y == previousViewport.y) return;
+	
+	hh_ppu_update_aux((hh_s_ppu_loc_aux){
+		.bg_shift_x = viewport.x*HH_PPU_SPRITE_WIDTH,
+		.bg_shift_y = viewport.y*HH_PPU_SPRITE_HEIGHT,
+		.fg_fetch	= 0,
+		.sysreset	= 0,
+	});
+
+	// update previous viewport values
+	previousViewport = viewport;
+}
+
+void hh_setup_screen(){
+	//(HH_map_size_X*HH_map_size_Y)
+	int size = 3200; // max X = 40 en max Y = 80
+	FILE* level = fopen("../test/bin/test_map.bin", "rb"); /* open binary file */
+	if (!level) { /* check if file opened successfully */
+		fprintf(stderr, "Error: Failed to open file.\n");
+		return;
+	}
+	fseek(level, (0* sizeof(int)) + sizeof(int), SEEK_SET);
+	int* tile = (int*)malloc(size*sizeof(int));
+   fread(tile, sizeof(int), size, level); // read 1 tile from binary
+
+	fclose(level);
+
+	for(int BAM_index = 0; BAM_index < size; BAM_index++){
+		hh_ppu_update_background(BAM_index, (hh_s_ppu_loc_bam_entry){
+			.horizontal_flip = false,
+			.vertical_flip   = false,
+			.palette_index   = tile[BAM_index]+1,
+			.tilemap_index   = tile[BAM_index],
+		});
+	}
+	free(tile);
+}
diff --git a/src/engine/draw_screen.h b/src/engine/draw_screen.h
index 4af5865..8d7df47 100644
--- a/src/engine/draw_screen.h
+++ b/src/engine/draw_screen.h
@@ -2,8 +2,20 @@
 
 
 // every function call for drawing the screen goes here.
-#include "engine/maths.h"
+#include "../engine/maths.h"
+#include "ppu/ppu.h"
 
+#include <stdio.h>
 #include <stdint.h>
-uint16_t hh_world_to_tile(vec2 pos);
-void hh_draw_screen(vec2 viewport);
-\ No newline at end of file
+#include <stdlib.h>
+
+
+#define HH_map_size_X 80
+#define HH_map_size_Y 60
+
+/** @brief return a single tile from world binary */
+uint8_t hh_world_to_tile(vec2 pos);
+/** @brief shift to level if viewport changed position */
+void hh_draw_screen(vec2 viewport);
+/** @brief send data to BAM memory from binary level */
+void hh_setup_screen();
diff --git a/src/makefile b/src/makefile
index 96751fb..96f3108 100644
--- a/src/makefile
+++ b/src/makefile
@@ -31,7 +31,8 @@ LOCAL_SRCS += main.c \
 							ppu/internals.c \
 							ppu/ppu.c \
 							demo.c \
-							engine/engine.c
+							engine/engine.c \
+							engine/draw_screen.c
 
 CFLAGS += $(SHARED_FLAGS)
 LFLAGS += $(SHARED_FLAGS)