Fix T90855: Transform effect gives inconsistent output

When using downscaled preview size with proxies, transform effect
doesn't compensate for fact, that pixels are effectively larger. There
was compensation for scene render size already.

Use same compensation method as text effect uses for font size.

1 files changed, 7 insertions, 4 deletions

diff --git a/source/blender/sequencer/intern/effects.c b/source/blender/sequencer/intern/effects.c
index 427a8835879..b9ee23a9186 100644
--- a/source/blender/sequencer/intern/effects.c
+++ b/source/blender/sequencer/intern/effects.c
@@ -2451,7 +2451,6 @@ static void do_transform_effect(const SeqRenderData *context,
                                 int total_lines,
                                 ImBuf *out)
 {
-  Scene *scene = context->scene;
   TransformVars *transform = (TransformVars *)seq->effectdata;
   float scale_x, scale_y, translate_x, translate_y, rotate_radians;
 
@@ -2469,10 +2468,14 @@ static void do_transform_effect(const SeqRenderData *context,
 
   /* Translate */
   if (!transform->percent) {
-    float rd_s = (scene->r.size / 100.0f);
+    /* Compensate text size for preview render size. */
+    double proxy_size_comp = context->scene->r.size / 100.0;
+    if (context->preview_render_size != SEQ_RENDER_SIZE_SCENE) {
+      proxy_size_comp = SEQ_rendersize_to_scale_factor(context->preview_render_size);
+    }
 
-    translate_x = transform->xIni * rd_s + (x / 2.0f);
-    translate_y = transform->yIni * rd_s + (y / 2.0f);
+    translate_x = transform->xIni * proxy_size_comp + (x / 2.0f);
+    translate_y = transform->yIni * proxy_size_comp + (y / 2.0f);
   }
   else {
     translate_x = x * (transform->xIni / 100.0f) + (x / 2.0f);