Finally, it's working properly, great! But the FPS is very low. Did I do something wrong?

[Leewx820]

Hi, @elishacloud.
Two years ago, I mentioned in #241 that I tried using dxwrapper in Mir3. Although it could barely work after debugging, after a series of tests, many problems still occurred, which made me give up on this issue. Today, when I checked dxwrapper, I found that it has been updated a lot in these two years. I tried using dxwrapper again in Mir3, and this time it worked very smoothly. It's amazing, but there is still one problem, which is low FPS and the game runs very slowly. Of course, this is also the case when not using dxwrapper. I naturally thought that converting ddraw to directx9 with dxwrapper would bring a significant improvement. I tried different settings, but it seems that this problem cannot be solved. Could you please help me solve this problem? I can provide the information you need.

This is my device information
Device name DESKTOP-RTU3N9V
Processor AMD Ryzen 7 9800X3D 8-Core Processor 5.40 GHz
Machine RAM 96.0 GB (95.6 GB available)
Storage 1.86 TB SSD ZHITAI TiPro9000 2TB, 932 GB SSD Samsung SSD 970 EVO Plus 1TB
Graphics Card NVIDIA GeForce RTX 5090 (31 GB)

System Information
Version Windows 10 Enterprise LTSC
Version Number 21H2
Installation Date ‎2025/‎6/‎12
OS Internal Version 19044.6809

Not using dxwrapper

Using dxwrapper

[Leewx820]

The program uses a lot of GPU performance, but the game speed has not changed at all.

[elishacloud]

Glad it is working for you.

Two options you can try is enabling DdrawUseShadowSurface and setting DdrawOverrideStencilFormat to 75. That helps speed up some games.

[Dd7to9]
DdrawUseShadowSurface      = 1
DdrawOverrideStencilFormat = 75

If that doesn't work you can try forcing vsync off using the following settings:

EnableVSync                = 0
ForceVsyncMode             = 1

[Leewx820]

Yes, after the above settings, FPS has improved significantly. However, it seems that the GPU's rendering performance is still not fully utilized. I have found that text rendering has a significant impact on performance. When opening NPCs in the game, FPS drops sharply. I previously analyzed the game, and it uses TextOut for text output. It seems the problem lies here. Are there other solutions to optimize this issue?

[elishacloud]

I don't think there is much that can be done without code changes. I'd need to check how the text is getting displayed and where the slowdown is coming from.

You could get me a profiling log of the slowdown using this build, which should help me isolate the issue: dxwrapper.zip

[Leewx820]

log.zip
This is the log after running, I hope it can help you troubleshoot the issue.

[Leewx820]

I verified my hypothesis by directly returning without drawing text, but unfortunately, it seems the problem is not what I thought. Even when text is no longer drawn, the FPS remains almost unchanged. It appears that text rendering is not the key factor affecting drawing performance

[elishacloud]

Unfortunately, there is no smoking gun here. This game calls hundreds of Lock()/GetDC() functions per frame. These are very slow calls when requesting video memory. What's worse is the game is calling the functions on a single surface. This prevents any multi-threading that could be done if multiple surfaces were being locked.

Probably the best thing you can do is lower the resolution. The larger the resolutions mean more data needs to move from video RAM to system RAM each lock cycle.

You could also try enabling the options below. However, be careful with these options as enabling them can easily cause the game to crash.

DdrawNoDrawBufferSysLock   = 1
DdrawNoMultiThreaded       = 1

[Leewx820]

Your last reply gave me an idea. By reverse-engineering the game's logic, I found that each texture drawing used Lock/Unlock, which was one of the main reasons for the game's slow performance. I wrote a standalone hook library to try merging the Lock/Unlock operations, which perfectly solved this problem. Now the game runs at several times the previous frame rate! Thank you for everything you did!

[elishacloud]

That's great. Glad you got it working. If you can put the code into a GitHub repository you can link it back to this issue. This kind of code may be useful for other games or I can integrate something similar into dxwrapper.

[Leewx820]

My pleasure. Although this code is not universal, it may offer some ideas for people facing the same problem.

DDHook.zip

[Leewx820]

I have a question. After converting DX7 to DX9 using dxwrapper, is there a way for me to obtain the interface of the converted DX9?