libui/GTK: fix drawmatrix transform order to match Windows. fixes rotation.

2 files changed, 16 insertions, 10 deletions

diff --git a/src/libui_sdl/libui/unix/drawmatrix.c b/src/libui_sdl/libui/unix/drawmatrix.c
index ac7ac57..f12b303 100644
--- a/src/libui_sdl/libui/unix/drawmatrix.c
+++ b/src/libui_sdl/libui/unix/drawmatrix.c
@@ -25,35 +25,41 @@ static void c2m(cairo_matrix_t *c, uiDrawMatrix *m)
 void uiDrawMatrixTranslate(uiDrawMatrix *m, double x, double y)
 {
 	cairo_matrix_t c;
+	cairo_matrix_t tmp;
 
 	m2c(m, &c);
-	cairo_matrix_translate(&c, x, y);
+	cairo_matrix_init_translate(&tmp, x, y);
+	cairo_matrix_multiply(&c, &c, &tmp);
 	c2m(&c, m);
 }
 
 void uiDrawMatrixScale(uiDrawMatrix *m, double xCenter, double yCenter, double x, double y)
 {
 	cairo_matrix_t c;
+	cairo_matrix_t tmp;
 	double xt, yt;
 
 	m2c(m, &c);
 	xt = x;
 	yt = y;
 	scaleCenter(xCenter, yCenter, &xt, &yt);
-	cairo_matrix_translate(&c, xt, yt);
-	cairo_matrix_scale(&c, x, y);
-	cairo_matrix_translate(&c, -xt, -yt);
+	cairo_matrix_init_translate(&tmp, xt, yt);
+	cairo_matrix_scale(&tmp, x, y);
+	cairo_matrix_translate(&tmp, -xt, -yt);
+	cairo_matrix_multiply(&c, &c, &tmp);
 	c2m(&c, m);
 }
 
 void uiDrawMatrixRotate(uiDrawMatrix *m, double x, double y, double amount)
 {
 	cairo_matrix_t c;
+	cairo_matrix_t tmp;
 
 	m2c(m, &c);
-	cairo_matrix_translate(&c, x, y);
-	cairo_matrix_rotate(&c, amount);
-	cairo_matrix_translate(&c, -x, -y);
+	cairo_matrix_init_translate(&tmp, x, y);
+	cairo_matrix_rotate(&tmp, amount);
+	cairo_matrix_translate(&tmp, -x, -y);
+	cairo_matrix_multiply(&c, &c, &tmp);
 	c2m(&c, m);
 }
 
diff --git a/src/libui_sdl/main.cpp b/src/libui_sdl/main.cpp
index 110dd25..34d0760 100644
--- a/src/libui_sdl/main.cpp
+++ b/src/libui_sdl/main.cpp
@@ -594,7 +594,7 @@ void SetupScreenRects(int width, int height)
 
     switch (ScreenRotation)
     {
-    case 1: // 90\B0
+    case 1: // 90°
         {
             uiDrawMatrixTranslate(&TopScreenTrans, -TopScreenRect.X, -TopScreenRect.Y);
             uiDrawMatrixRotate(&TopScreenTrans, 0, 0, M_PI/2.0f);
@@ -612,7 +612,7 @@ void SetupScreenRects(int width, int height)
         }
         break;
 
-    case 2: // 180\B0
+    case 2: // 180°
         {
             uiDrawMatrixTranslate(&TopScreenTrans, -TopScreenRect.X, -TopScreenRect.Y);
             uiDrawMatrixRotate(&TopScreenTrans, 0, 0, M_PI);
@@ -624,7 +624,7 @@ void SetupScreenRects(int width, int height)
         }
         break;
 
-    case 3: // 270\B0
+    case 3: // 270°
         {
             uiDrawMatrixTranslate(&TopScreenTrans, -TopScreenRect.X, -TopScreenRect.Y);
             uiDrawMatrixRotate(&TopScreenTrans, 0, 0, -M_PI/2.0f);