gg: move code using C types to c.v files, add js.v files (#12873)

vlib/gg/image.c.v

@@ -5,6 +5,22 @@ module gg
 import os
 import stbi
 import sokol.gfx
+import sokol.sgl
+
+[heap]
+pub struct Image {
+pub mut:
+	id          int
+	width       int
+	height      int
+	nr_channels int
+	ok          bool
+	data        voidptr
+	ext         string
+	simg_ok     bool
+	simg        C.sg_image
+	path        string
+}
 
 // TODO return ?Image
 pub fn (mut ctx Context) create_image(file string) Image {
@@ -165,3 +181,126 @@ pub fn (mut ctx Context) create_image_with_size(file string, width int, height i
 	ctx.image_cache << img
 	return img
 }
+
+// TODO remove this
+fn create_image(file string) Image {
+	if !os.exists(file) {
+		println('gg.create_image(): file not found: $file')
+		return Image{} // none
+	}
+	stb_img := stbi.load(file) or { return Image{} }
+	mut img := Image{
+		width: stb_img.width
+		height: stb_img.height
+		nr_channels: stb_img.nr_channels
+		ok: stb_img.ok
+		data: stb_img.data
+		ext: stb_img.ext
+		path: file
+	}
+	img.init_sokol_image()
+	return img
+}
+
+pub fn (mut ctx Context) create_image_from_memory(buf &byte, bufsize int) Image {
+	stb_img := stbi.load_from_memory(buf, bufsize) or { return Image{} }
+	mut img := Image{
+		width: stb_img.width
+		height: stb_img.height
+		nr_channels: stb_img.nr_channels
+		ok: stb_img.ok
+		data: stb_img.data
+		ext: stb_img.ext
+		id: ctx.image_cache.len
+	}
+	ctx.image_cache << img
+	return img
+}
+
+pub fn (mut ctx Context) create_image_from_byte_array(b []byte) Image {
+	return ctx.create_image_from_memory(b.data, b.len)
+}
+
+pub struct StreamingImageConfig {
+	pixel_format gfx.PixelFormat = .rgba8
+	wrap_u       gfx.Wrap        = .clamp_to_edge
+	wrap_v       gfx.Wrap        = .clamp_to_edge
+	min_filter   gfx.Filter      = .linear
+	mag_filter   gfx.Filter      = .linear
+	num_mipmaps  int = 1
+	num_slices   int = 1
+}
+
+// draw_image_with_config takes in a config that details how the
+// provided image should be drawn onto the screen
+pub fn (ctx &Context) draw_image_with_config(config DrawImageConfig) {
+	id := if !isnil(config.img) { config.img.id } else { config.img_id }
+	if id >= ctx.image_cache.len {
+		eprintln('gg: draw_image() bad img id $id (img cache len = $ctx.image_cache.len)')
+		return
+	}
+
+	img := &ctx.image_cache[id]
+	if !img.simg_ok {
+		return
+	}
+
+	mut img_rect := config.img_rect
+	if img_rect.width == 0 && img_rect.height == 0 {
+		img_rect = Rect{img_rect.x, img_rect.y, img.width, img.height}
+	}
+
+	mut part_rect := config.part_rect
+	if part_rect.width == 0 && part_rect.height == 0 {
+		part_rect = Rect{part_rect.x, part_rect.y, img.width, img.height}
+	}
+
+	u0 := part_rect.x / img.width
+	v0 := part_rect.y / img.height
+	u1 := (part_rect.x + part_rect.width) / img.width
+	v1 := (part_rect.y + part_rect.height) / img.height
+	x0 := img_rect.x * ctx.scale
+	y0 := img_rect.y * ctx.scale
+	x1 := (img_rect.x + img_rect.width) * ctx.scale
+	mut y1 := (img_rect.y + img_rect.height) * ctx.scale
+	if img_rect.height == 0 {
+		scale := f32(img.width) / f32(img_rect.width)
+		y1 = f32(img_rect.y + int(f32(img.height) / scale)) * ctx.scale
+	}
+
+	flip_x := config.flip_x
+	flip_y := config.flip_y
+
+	mut u0f := if !flip_x { u0 } else { u1 }
+	mut u1f := if !flip_x { u1 } else { u0 }
+	mut v0f := if !flip_y { v0 } else { v1 }
+	mut v1f := if !flip_y { v1 } else { v0 }
+
+	sgl.load_pipeline(ctx.timage_pip)
+	sgl.enable_texture()
+	sgl.texture(img.simg)
+
+	if config.rotate != 0 {
+		width := img_rect.width * ctx.scale
+		height := (if img_rect.height > 0 { img_rect.height } else { img.height }) * ctx.scale
+
+		sgl.push_matrix()
+		sgl.translate(x0 + (width / 2), y0 + (height / 2), 0)
+		sgl.rotate(sgl.rad(-config.rotate), 0, 0, 1)
+		sgl.translate(-x0 - (width / 2), -y0 - (height / 2), 0)
+	}
+
+	sgl.begin_quads()
+	sgl.c4b(config.color.r, config.color.g, config.color.b, config.color.a)
+	sgl.v3f_t2f(x0, y0, config.z, u0f, v0f)
+	sgl.v3f_t2f(x1, y0, config.z, u1f, v0f)
+	sgl.v3f_t2f(x1, y1, config.z, u1f, v1f)
+	sgl.v3f_t2f(x0, y1, config.z, u0f, v1f)
+	sgl.end()
+
+	if config.rotate != 0 {
+		sgl.pop_matrix()
+	}
+
+	sgl.disable_texture()
+}