Framebuffer cleanup and areas

src/kernel/drivers/framebuffer.c

@@ -2,30 +2,80 @@
 #include <memory.h>
 #include <multiboot.h>
 
+struct gfx_context {
+    uint32_t width;
+    uint32_t height;
+    uint32_t bpp;
+    uint32_t pitch;
+    void *addr;
+    void *buffer;
+    size_t size;
+};
+
+struct gfx_context framebuffer;
+
+struct gfx_context subcontext;
+
+#define RGB(r, g, b) (((uint32_t) (r<<16) + (g<<8) + (b)))
+
+void putpixel(struct gfx_context *ctx, uint64_t x, uint64_t y, uint32_t clr)
+{
+    if(x >= ctr->width || y >= ctx->height) return;
+    uint64_t loc = \
+        y * ctx->pitch + \
+        x * ctx->bpp/8;
+    uint32_t *fb = incptr(P2V(ctx->addr), loc);
+
+    *fb = clr;
+}
+
+static void draw_border(struct gfx_context *ctx, uint32_t clr)
+{
+    for(uint64_t x = 0; x < ctx->width; x++)
+    {
+        putpixel(ctx, x, 0, clr);
+        putpixel(ctx, x, ctx->height-1, clr);
+    }
+    for(uint64_t y = 0; y < ctx->height; y++)
+    {
+        putpixel(ctx, 0, y, clr);
+        putpixel(ctx, ctx->width-1, y, clr);
+    }
+}
+
+struct gfx_context *make_subarea(struct gfx_context *ctx, uint64_t x, uint64_t y, uint64_t width, uint64_t height)
+{
+    struct gfx_context *out = &subcontext;
+    uint64_t loc = \
+        y * ctx->pitch + \
+        x * ctx->bpp/8;
+
+    out->width = width;
+    out->height = height;
+    out->bpp = ctx->bpp;
+    out->pitch = ctx->pitch;
+    out->addr = incptr(ctx->addr, loc);
+    out->size = ctx->pitch * (height);
+
+    return out;
+}
+
 void framebuffer_init(struct fbinfo *fbinfo)
 {
-    size_t fb_size = fbinfo->framebuffer_pitch * (fbinfo->framebuffer_height+1);
-    uintptr_t fb_end = fbinfo->framebuffer_addr + fb_size;
+    framebuffer.width = fbinfo->framebuffer_width;
+    framebuffer.height = fbinfo->framebuffer_height;
+    framebuffer.bpp = fbinfo->framebuffer_bpp;
+    framebuffer.pitch = fbinfo->framebuffer_pitch;
+    framebuffer.addr = (void *)fbinfo->framebuffer_addr;
+    framebuffer.size = framebuffer.pitch * (framebuffer.height);
 
-    for(uintptr_t p = fbinfo->framebuffer_addr; p < fb_end; p += PAGE_SIZE)
+    for(uintptr_t p = (uintptr_t)framebuffer.addr; p < ((uintptr_t)framebuffer.addr + framebuffer.size); p += PAGE_SIZE)
     {
         vmm_set_page(kernel_P4, (uint64_t)P2V(p), p, PAGE_WRITE | PAGE_PRESENT);
     }
 
-    uint8_t *fb = P2V(fbinfo->framebuffer_addr);
-
-    for(uint32_t y = 0; y < 1; y++)
-    {
-        for(uint32_t x = 0; x < fbinfo->framebuffer_width; x++)
-        {
-            unsigned int bpp = fbinfo->framebuffer_bpp/8;
-            unsigned int loc = \
-                y*fbinfo->framebuffer_pitch + \
-                x*(bpp);
-            fb[loc++] = 0xFF;
-            fb[loc++] = 0;
-            fb[loc] = 0xFF;
-        }
-    }
+    draw_border(&framebuffer, RGB(0, 255, 0));
+    struct gfx_context *sub = make_subarea(&framebuffer, 256, 192, 256, 192);
+    draw_border(sub, RGB(255, 0, 0));
 
 }