Change: programs->utils

src/utils/bmp.c

@@ -0,0 +1,99 @@
+// Bitmap image renderer
+// Author: xamidev
+// Licensed under the Unlicense. See the repo below.
+// https://github.com/xamidev/blankos
+
+#include "../kernel/kmain.h"
+#include <stdint.h>
+#include "../kernel/initrd.h"
+#include "../drivers/framebuffer.h"
+#include "../libc/stdio.h"
+#include "../drivers/serial.h"
+#include "../kernel/kheap.h"
+
+#pragma pack(push, 1)
+typedef struct
+{
+	uint16_t bfType;
+	uint32_t bfSize;
+	uint16_t bfReserved1;
+	uint16_t bfReserved2;
+	uint32_t bfOffBits;
+} BMPHeader;
+
+typedef struct
+{
+	uint32_t biSize;
+	int32_t  biWidth;
+	int32_t  biHeight;
+	uint16_t biPlanes;
+	uint16_t biBitCount;
+	uint32_t biCompression;
+	uint32_t biSizeImage;
+	int32_t  biXPelsPerMeter;
+	int32_t  biYPelsPerMeter;
+	uint32_t biClrUsed;
+	uint32_t biClrImportant;
+} BMPInfoHeader;
+#pragma pack(pop)
+
+void display_bmp(uint32_t* fb, int pitch, int bpp, uint8_t* initrd, const char* filename)
+{
+	uint32_t buf_size = tar_get_file_size(initrd, filename);
+	char* buffer = (char*)malloc(buf_size);
+	int file_status = tar_file_to_buffer(initrd, filename, buffer);
+
+	if (file_status != 0)
+	{
+		printf("Error loading file '%s'\n", filename);
+		return;
+	}
+
+	BMPHeader* bmp_header = (BMPHeader*)buffer;
+	BMPInfoHeader* bmp_info = (BMPInfoHeader*) (buffer+sizeof(BMPHeader));
+
+	if (bmp_header->bfType != 0x4D42)
+	{
+		printf("'%s' is not a valid BMP file\n", filename);
+		return;
+	}
+
+	int width = bmp_info->biWidth;
+	int height = bmp_info->biHeight;
+	int pixel_offset = bmp_header->bfOffBits;
+
+	printf("%d-bit BMP, width: %d, height: %d, pixel offset: %d\n", bmp_info->biBitCount, bmp_info->biWidth, bmp_info->biHeight, (int)bmp_header->bfOffBits);	
+	erase_cursor();
+	uint8_t* pixel_data = (uint8_t*)(buffer + pixel_offset);
+
+	int cursor_y = (get_cursor_y()+1)*16;
+	serial_printf(3, "cursor_y=%d\n", cursor_y);
+
+	for (int y=cursor_y; y<height+cursor_y; y++)
+	{
+		for (int x=0; x<width; x++)
+		{
+			int index = (x+(height-y-1+cursor_y)*width)*3;
+			uint8_t blue = pixel_data[index];
+			uint8_t green = pixel_data[index+1];
+			uint8_t red = pixel_data[index+2];
+
+			uint32_t color = (0xFF << 24) | (red << 16) | (green << 8) | blue;
+			putpixel(fb, pitch, bpp, x, y, color);
+		}
+	}
+
+	// Update cursor pos after image drawing
+	move_cursor(get_cursor_x(), get_cursor_y()+(height/16)+2);
+	free(buffer);
+}
+
+void program_bmp(int argc, char* argv[])
+{
+	if (argc < 2)
+	{
+		puts("Usage: bmp <file>\n"); 
+		return;
+	}
+	display_bmp(framebuffer, pitch, bpp, (uint8_t*)initrd_addr, argv[1]);
+}