Initial project import

tools/v/vlib/x/ttf/text_block.v

@@ -0,0 +1,123 @@
+module ttf
+
+/**********************************************************************
+*
+* BMP render module utility functions
+*
+* Copyright (c) 2021 Dario Deledda. All rights reserved.
+* Use of this source code is governed by an MIT license
+* that can be found in the LICENSE file.
+*
+* Note:
+*
+* TODO:
+**********************************************************************/
+// Text_block represents a visual block of TTF text.
+pub struct Text_block {
+pub:
+	x         int // x position of the left high corner
+	y         int // y position of the left high corner
+	w         int // width of the text block
+	h         int // height of the text block
+	cut_lines bool = true // force to cut the line if the length is over the text block width
+}
+
+// get_justify_space_cw returns the space needed to justify `txt`.
+pub fn (mut dev BitMap) get_justify_space_cw(txt string, w int, block_w int, space_cw int) f32 {
+	num_spaces := txt.count(' ')
+	if num_spaces < 1 {
+		return 0
+	}
+	delta := block_w - w
+	// println("num spc: ${num_spaces}")
+	// println("delta: ${txt} w:${w} bw:${block_w} space_cw:${space_cw}")
+	res := f32(delta) / f32(num_spaces) / f32(space_cw)
+	// println("res: ${res}")
+	return res
+}
+
+// draw_text_block renders out `text` in the `Text_block` `block`.
+pub fn (mut bmp BitMap) draw_text_block(text string, block Text_block) {
+	mut x := block.x
+	mut y := block.y
+	mut y_base := int((bmp.tf.y_max - bmp.tf.y_min) * bmp.scale)
+
+	// bmp.box(x, y, x + block.w, y + block.h, u32(0xFF00_0000))
+
+	// spaces data
+	mut space_cw, _ := bmp.tf.get_horizontal_metrics(u16(` `))
+	space_cw = int(space_cw * bmp.scale)
+
+	old_space_cw := bmp.space_cw
+
+	mut offset_flag := f32(0) // default .left align
+	if bmp.align == .right {
+		offset_flag = 1
+	} else if bmp.align == .center {
+		offset_flag = 0.5
+	}
+
+	for txt in text.split_into_lines() {
+		bmp.space_cw = old_space_cw
+		mut w, _ := bmp.get_bbox(txt)
+		if w <= block.w || block.cut_lines == false {
+			// println("Solid block!")
+			left_offset := int((block.w - w) * offset_flag)
+			if bmp.justify && (f32(w) / f32(block.w)) >= bmp.justify_fill_ratio {
+				bmp.space_cw = old_space_cw + bmp.get_justify_space_cw(txt, w, block.w, space_cw)
+			}
+			bmp.set_pos(x + left_offset, y + y_base)
+			bmp.draw_text(txt)
+			//---- DEBUG ----
+			// mut txt_w , mut txt_h := bmp.draw_text(txt)
+			// bmp.box(x + left_offset,y+y_base - int((bmp.tf.y_min)*bmp.scale), x + txt_w + left_offset, y + y_base - int((bmp.tf.y_max) * bmp.scale), u32(0x00ff_0000) )
+			//---------------
+			y += y_base
+		} else {
+			// println("to cut: ${txt}")
+			mut txt1 := txt.split(' ')
+			mut c := txt1.len
+			// mut done := false
+			for c > 0 {
+				tmp_str := txt1[0..c].join(' ')
+				// println("tmp_str: ${tmp_str}")
+				if tmp_str == '' {
+					break
+				}
+
+				bmp.space_cw = old_space_cw
+				w, _ = bmp.get_bbox(tmp_str)
+				if w <= block.w {
+					mut left_offset := int((block.w - w) * offset_flag)
+					if bmp.justify && (f32(w) / f32(block.w)) >= bmp.justify_fill_ratio {
+						// println("cut phase!")
+						bmp.space_cw = 0.0
+						w, _ = bmp.get_bbox(tmp_str)
+						left_offset = int((block.w - w) * offset_flag)
+						bmp.space_cw = bmp.get_justify_space_cw(tmp_str, w, block.w, space_cw)
+					} else {
+						bmp.space_cw = old_space_cw
+					}
+					bmp.set_pos(x + left_offset, y + y_base)
+					bmp.draw_text(tmp_str)
+					//---- DEBUG ----
+					// txt_w , txt_h := bmp.draw_text(tmp_str)
+					// println("printing [${x},${y}] => '${tmp_str}' space_cw: ${bmp.space_cw}")
+					// bmp.box(x + left_offset,y + y_base - int((bmp.tf.y_min)*bmp.scale), x + txt_w + left_offset, y + y_base - int((bmp.tf.y_max) * bmp.scale), u32(0x00ff_0000) )
+					//---------------
+					y += y_base
+					txt1 = unsafe { txt1[c..] }
+					c = txt1.len
+					//---- DEBUG ----
+					// txt2 := txt1.join(' ')
+					// println("new string: ${txt2} len: ${c}")
+					//---------------
+				} else {
+					c--
+				}
+			}
+		}
+	}
+
+	bmp.space_cw = old_space_cw
+}