[Bf-blender-cvs] [cb8da6efce8] master: GPUState: Fix scissor state being overwritten when changing scissor bounds

[Clément Foucault]

Commit: cb8da6efce80932797aaf3e10aa7eb8f3474c1ae
Author: Clément Foucault
Date:   Mon Aug 24 12:28:54 2020 +0200
Branches: master
https://developer.blender.org/rBcb8da6efce80932797aaf3e10aa7eb8f3474c1ae

GPUState: Fix scissor state being overwritten when changing scissor bounds

Fix T79899 viewport artifacts when sculpting

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M	source/blender/gpu/intern/gpu_state.cc

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diff --git a/source/blender/gpu/intern/gpu_state.cc b/source/blender/gpu/intern/gpu_state.cc
index f8d753f9ee7..fcbaa500e2d 100644
--- a/source/blender/gpu/intern/gpu_state.cc
+++ b/source/blender/gpu/intern/gpu_state.cc
@@ -201,7 +201,8 @@ void GPU_scissor(int x, int y, int width, int height)
 {
   GPUStateManager *stack = GPU_context_active_get()->state_manager;
   auto &state = stack->mutable_state;
-  int scissor_rect[4] = {x, y, width, height};
+  bool enabled = state.scissor_rect[2] > 0;
+  int scissor_rect[4] = {x, y, enabled ? width : -width, height};
   copy_v4_v4_int(state.scissor_rect, scissor_rect);
 }