progres

Signed-off-by: Slendi <slendi@socopon.com>

src/TextRenderer.cpp

@@ -164,8 +164,10 @@ auto TextRenderer::generate_glyph(FontRuntime &rt, FontData &fd,
 
 	msdfgen::Bitmap<float, 3> msdf_bitmap(bmp_w, bmp_h);
 	msdfgen::Vector2 scale_vec(scale, scale);
+	double const inv_scale = 1.0 / scale;
 	msdfgen::Vector2 translate(
-	    -bounds.l * scale + rt.px_range, -bounds.b * scale + rt.px_range);
+	    -bounds.l + rt.px_range * inv_scale,
+	    -bounds.b + rt.px_range * inv_scale);
 	msdfgen::generateMSDF(msdf_bitmap, shape, rt.px_range, scale_vec, translate);
 
 	std::vector<Color> buffer(static_cast<size_t>(bmp_w) * bmp_h);

tools/dump_msdf.cpp

@@ -0,0 +1,85 @@
+#include <cstdio>
+#include <cstdlib>
+#include <cmath>
+#include <vector>
+#include <string>
+
+#include <msdfgen.h>
+#include <ext/import-font.h>
+
+static unsigned char clamp_channel(float v) {
+    if (v <= 0.0f) return 0;
+    if (v >= 1.0f) return 255;
+    return static_cast<unsigned char>(std::lround(v * 255.0f));
+}
+
+int main(int argc, char **argv) {
+    if (argc < 3) {
+        std::fprintf(stderr, "Usage: %s <font-file> <codepoint>\n", argv[0]);
+        return 1;
+    }
+    const char *fontPath = argv[1];
+    unsigned codepoint = std::strtoul(argv[2], nullptr, 0);
+    auto *ft = msdfgen::initializeFreetype();
+    if (!ft) return 1;
+    auto *font = msdfgen::loadFont(ft, fontPath);
+    if (!font) return 1;
+    msdfgen::Shape shape;
+    double advance = 0.0;
+    if (!msdfgen::loadGlyph(shape, font, msdfgen::GlyphIndex(codepoint), msdfgen::FONT_SCALING_EM_NORMALIZED, &advance)) {
+        std::fprintf(stderr, "Failed to load glyph %u\n", codepoint);
+        return 1;
+    }
+    shape.normalize();
+    msdfgen::edgeColoringSimple(shape, 3.0);
+    auto bounds = shape.getBounds();
+
+    double emScale = 48.0;
+    double pxRange = 4.0;
+    int bmp_w = std::max(1, (int)std::ceil((bounds.r - bounds.l) * emScale + 2.0 * pxRange));
+    int bmp_h = std::max(1, (int)std::ceil((bounds.t - bounds.b) * emScale + 2.0 * pxRange));
+
+    msdfgen::Bitmap<float, 3> bitmap(bmp_w, bmp_h);
+    msdfgen::Vector2 scale(emScale, emScale);
+    msdfgen::Vector2 translate(-bounds.l * emScale + pxRange, -bounds.b * emScale + pxRange);
+    msdfgen::generateMSDF(bitmap, shape, pxRange, scale, translate);
+
+    std::vector<unsigned char> buffer(static_cast<size_t>(bmp_w) * bmp_h * 4);
+    for (int y = 0; y < bmp_h; ++y) {
+        int dst_y = bmp_h - 1 - y;
+        for (int x = 0; x < bmp_w; ++x) {
+            const float *px = bitmap(x, y);
+            size_t idx = (static_cast<size_t>(dst_y) * bmp_w + x) * 4;
+            buffer[idx + 0] = clamp_channel(px[0]);
+            buffer[idx + 1] = clamp_channel(px[1]);
+            buffer[idx + 2] = clamp_channel(px[2]);
+            buffer[idx + 3] = 255;
+        }
+    }
+
+    int minX = bmp_w, minY = bmp_h, maxX = -1, maxY = -1;
+    for (int y = 0; y < bmp_h; ++y) {
+        for (int x = 0; x < bmp_w; ++x) {
+            size_t idx = (static_cast<size_t>(y) * bmp_w + x) * 4;
+            unsigned char r = buffer[idx];
+            unsigned char g = buffer[idx + 1];
+            unsigned char b = buffer[idx + 2];
+            bool interesting = !(r == 0 && g == 0 && b == 0) && !(r == 255 && g == 255 && b == 255);
+            if (interesting) {
+                if (x < minX) minX = x;
+                if (x > maxX) maxX = x;
+                if (y < minY) minY = y;
+                if (y > maxY) maxY = y;
+            }
+        }
+    }
+
+    std::printf("bmp %dx%d\n", bmp_w, bmp_h);
+    if (maxX >= minX && maxY >= minY) {
+        std::printf("interesting bbox: x=[%d,%d] y=[%d,%d]\n", minX, maxX, minY, maxY);
+    }
+
+    msdfgen::destroyFont(font);
+    msdfgen::deinitializeFreetype(ft);
+    return 0;
+}