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-rw-r--r--graphics/primitives.cpp55
-rw-r--r--graphics/primitives.h1
2 files changed, 56 insertions, 0 deletions
diff --git a/graphics/primitives.cpp b/graphics/primitives.cpp
index 9fdcb13b7b..85a0383ea9 100644
--- a/graphics/primitives.cpp
+++ b/graphics/primitives.cpp
@@ -64,4 +64,59 @@ void drawLine(int x0, int y0, int x1, int y1, int color, void (*plotProc)(int, i
}
}
+
+// FIXME: This is a limited version of thick line drawing
+// it draws striped lines at some angles. Better algorithm could
+// be found here:
+//
+// http://homepages.enterprise.net/murphy/thickline/index.html
+//
+// Feel free to replace it with better implementation
+void drawThickLine(int x0, int y0, int x1, int y1, int thickness, int color, void (*plotProc)(int, int, int, void *), void *data) {
+ const bool steep = ABS(y1 - y0) > ABS(x1 - x0);
+
+ if (steep) {
+ SWAP(x0, y0);
+ SWAP(x1, y1);
+ }
+
+ float dx = x1 - x0;
+ float dy = y1 - y0;
+ float d = sqrtf(dx * dx + dy * dy);
+
+ if (!d)
+ return;
+
+ int thickX = (int)((float)thickness * dy / d / 2);
+ int thickY = (int)((float)thickness * dx / d / 2);
+
+ const int delta_x = ABS(x1 - x0);
+ const int delta_y = ABS(y1 - y0);
+ const int delta_err = delta_y;
+ int x = x0;
+ int y = y0;
+ int err = 0;
+
+ const int x_step = (x0 < x1) ? 1 : -1;
+ const int y_step = (y0 < y1) ? 1 : -1;
+
+ if (steep)
+ drawLine(y - thickY, x + thickX, y + thickY, x - thickX, color, plotProc, data);
+ else
+ drawLine(x - thickX, y + thickY, x + thickX, y - thickY, color, plotProc, data);
+
+ while (x != x1) {
+ x += x_step;
+ err += delta_err;
+ if (2 * err > delta_x) {
+ y += y_step;
+ err -= delta_x;
+ }
+ if (steep)
+ drawLine(y - thickY, x + thickX, y + thickY, x - thickX, color, plotProc, data);
+ else
+ drawLine(x - thickX, y + thickY, x + thickX, y - thickY, color, plotProc, data);
+ }
+}
+
} // End of namespace Graphics
diff --git a/graphics/primitives.h b/graphics/primitives.h
index 2bc44d6644..0c96c1545a 100644
--- a/graphics/primitives.h
+++ b/graphics/primitives.h
@@ -28,6 +28,7 @@
namespace Graphics {
void drawLine(int x0, int y0, int x1, int y1, int color, void (*plotProc)(int, int, int, void *), void *data);
+void drawThickLine(int x0, int y0, int x1, int y1, int thickness, int color, void (*plotProc)(int, int, int, void *), void *data);
} // End of namespace Graphics