From 3ef15b94aafa385171a0d83bafcb92693ee57041 Mon Sep 17 00:00:00 2001
From: condret <condr3t@protonmail.com>
Date: Tue, 1 Oct 2024 00:08:11 +0200
Subject: [PATCH] Add pixbuf api

---
 include/ragb_sdl.h | 21 +++++++++++++++
 sdl/pixbuf.c       | 64 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 85 insertions(+)
 create mode 100644 include/ragb_sdl.h
 create mode 100644 sdl/pixbuf.c

diff --git a/include/ragb_sdl.h b/include/ragb_sdl.h
new file mode 100644
index 0000000..f196f8e
--- /dev/null
+++ b/include/ragb_sdl.h
@@ -0,0 +1,21 @@
+#ifndef RAGB_SDL_H
+#define RAGB_SDL_H
+#include <r_util.h>
+#include <SDL2/SDL.h>
+
+typedef struct gb_pixel_buffer_t {
+	SDL_Renderer *renderer;
+	SDL_Texture *texture;
+	ut8 *buf;	//buffer containing pixeldata
+	ut32 color[4];	//rgb colors
+	ut16 w;		//x size in pixel
+	ut16 h;		//y size in pixel
+//	ut16 xsf;	//x scale factor for projecting onto the texture
+//	ut16 ysf;	//y scale factor for projecting onto the texture
+} GBPixBuf;
+
+GBPixBuf *gb_pix_buf_new(SDL_Renderer *renderer, ut16 w, ut16 h);
+void gb_pix_buf_free(GBPixBuf *pb);
+void gb_pix_buf_set_pixel(GBPixBuf *pb, ut16 x, ut16 y, ut8 pixval);
+void gb_pix_buf_set_color(GBPixBuf *pb, ut8 color_idx, ut32 rgb);
+#endif
diff --git a/sdl/pixbuf.c b/sdl/pixbuf.c
new file mode 100644
index 0000000..c1d9bf2
--- /dev/null
+++ b/sdl/pixbuf.c
@@ -0,0 +1,64 @@
+#include <ragb_sdl.h>
+#include <r_util.h>
+#include <SDL2/SDL.h>
+
+GBPixBuf *gb_pix_buf_new (SDL_Renderer *renderer, ut16 w, ut16 h) {
+	if (!renderer || !w || !h) {
+		return NULL;
+	}
+	GBPixBuf *pb = R_NEW (GBPixBuf);
+	if (!pb) {
+		return NULL;
+	}
+	const ut32 bitsize = w * h * 2;
+	const ut32 bytesize = (!!(bitsize & 0x7)) + (bitsize >> 3);
+	pb->buf = R_NEWS0 (ut8, bytesize);
+	if (!pb->buf) {
+		free (pb);
+		return NULL;
+	}
+	pb->texture = SDL_CreateTexture (renderer, SDL_PIXELFORMAT_ARGB32,
+		SDL_TEXTUREACCESS_TARGET, w, h);
+	if (!texture) {
+		free (pb->buf);
+		free (pb);
+		return NULL;
+	}
+	pb->w = w;
+	pb->h = h;
+	return pb;
+}
+
+void gb_pix_buf_free (GBPixBuf *pb) {
+	if (!pb) {
+		return;
+	}
+	SDL_DestroyTexture (pb->texture);
+	free (pb->buf);
+	free (pb);
+}
+
+void gb_pix_buf_set_pixel (GBPixBuf *pb, ut16 x, ut16 y, ut8 pixval) {
+	if (!pb) {
+		return;
+	}
+	const ut32 bitpos = (pb->w * y + x) * 2;
+	const ut32 bytepos = bitpos >> 3;
+	const ut32 shl = bitpos & 0x6;
+	pixval = pixval & 0x3;
+	const ut8 mask = ~(0x3 << shl)
+	pb->buf[bytepos] = (pb->buf[bytepos] & mask) | (pixval << shl);
+	SDL_Texture *target = SDL_GetRenderTarget (pb->renderer);
+	SDL_SetRenderTarget (pb->renderer, pb->texture);
+	SDL_SetRenderDrawColor (pb->renderer, (pb->color[pixval] >> 16) & 0xff,
+		(pb->color[pixval] >> 8) & 0xff, pb->color[pixval] & 0xff, 0xff);
+	SDL_RenderDrawPoint (pb->renderer, x, y);
+	SDL_SetRenderTarget (pb->renderer, target);
+}
+
+void gb_pix_buf_set_color (GBPixBuf *pb, ut8 color_idx, ut32 rgb) {
+	if (!pb) {
+		return;
+	}
+	pb->color[color_idx & 0x3] = rgb;
+}