migrate from nimPNG to stb_image

slightly faster screenshotting + smaller binaries

Author: cobaltgit

quark.nimble

@@ -7,7 +7,6 @@ license        = "GPL-3.0"
 srcDir         = "src"
 
 requires "nim >= 2.0.0"
-requires "nimPNG >= 0.3.1"
 
 const Root = getCurrentDir()
 const BinDir = Root / "dist" / "System" / "bin"

src/common/fb.nim

@@ -1,5 +1,5 @@
 import std/posix
-import nimPNG
+import ffi/stb/stb_image
 
 const
   FbWidth* = 240
@@ -66,4 +66,11 @@ proc fbscreenshot*(fbMap: pointer, output: string) =
       rotatedPixels[dstIdx + 2] = FiveToEight[b]
       rotatedPixels[dstIdx + 3] = 255
 
-  discard savePNG32(output, rotatedPixels, FbHeight, FbWidth)
+  discard stbi_write_png(
+    cstring(output),
+    cint(FbHeight),
+    cint(FbWidth),
+    cint(4),
+    addr rotatedPixels[0],
+    cint(FbHeight * 4)
+  )

src/common/ffi/stb/stb_image.c

@@ -0,0 +1,2 @@
+#define STB_IMAGE_IMPLEMENTATION
+#include "stb_image.h"

src/common/ffi/stb/stb_image.h

@@ -0,0 +1,24 @@
+import std/os
+
+{.compile("stb_image.c", "-O3").}
+{.compile("stb_image_write.c", "-O3").}
+{.passC: "-I" & currentSourcePath().splitPath().head.}
+
+proc stbi_load*(
+  filename: cstring,
+  x: ptr cint,
+  y: ptr cint,
+  channels_in_file: ptr cint,
+  desired_channels: cint
+): ptr uint8 {.importc, header: "stb_image.h".}
+
+proc stbi_write_png*(
+  filename: cstring,
+  w: cint,
+  h: cint,
+  comp: cint,
+  data: pointer,
+  stride_in_bytes: cint
+): cint {.importc, header: "stb_image_write.h".}
+
+proc stbi_image_free*(data: pointer) {.importc, header: "stb_image.h".}

src/common/ffi/stb/stb_image.nim

@@ -0,0 +1,2 @@
+#define STB_IMAGE_WRITE_IMPLEMENTATION
+#include "stb_image_write.h"