api: quality options for screen mirroring (#313)

## Link to GitHub Issue, if one exists
n/a

## Description of change
Allow the server to override client's quality options for screen
mirroring.

On Windows / Android versions (flutter-based) clients, this is already
in the options of those apps. However, the iOS version lacks the quality
options.

## Testing
Tested with iOS and Windows clients.

src/spice2x/api/modules/capture.cpp

@@ -9,6 +9,9 @@ using namespace rapidjson;
 
 namespace api::modules {
 
+    std::optional<uint32_t> CAPTURE_QUALITY;
+    std::optional<uint32_t> CAPTURE_DIVIDE;
+
     static thread_local std::vector<uint8_t> CAPTURE_BUFFER;
 
     Capture::Capture() : Module("capture") {
@@ -44,12 +47,21 @@ namespace api::modules {
         int screen = 0;
         int quality = 70;
         int divide = 1;
-        if (req.params.Size() > 0 && req.params[0].IsUint())
+        if (req.params.Size() > 0 && req.params[0].IsUint()) {
             screen = req.params[0].GetUint();
-        if (req.params.Size() > 1 && req.params[1].IsUint())
+        }
+
+        if (CAPTURE_QUALITY.has_value()) {
+            quality = CAPTURE_QUALITY.value();
+        } else if (req.params.Size() > 1 && req.params[1].IsUint()) {
             quality = req.params[1].GetUint();
-        if (req.params.Size() > 2 && req.params[2].IsUint())
+        }
+
+        if (CAPTURE_DIVIDE.has_value()) {
+            divide = CAPTURE_DIVIDE.value();
+        } else if (req.params.Size() > 2 && req.params[2].IsUint()) {
             divide = req.params[2].GetUint();
+        }
 
         // receive JPEG data
         uint64_t timestamp = 0;

src/spice2x/api/modules/capture.h

@@ -1,10 +1,15 @@
 #pragma once
 
+#include <optional>
+
 #include "api/module.h"
 #include "api/request.h"
 
 namespace api::modules {
 
+    extern std::optional<uint32_t> CAPTURE_QUALITY;
+    extern std::optional<uint32_t> CAPTURE_DIVIDE;
+
     class Capture : public Module {
     public:
         Capture();

src/spice2x/launcher/launcher.cpp

@@ -6,6 +6,7 @@
 #include <shlwapi.h>
 #include <cfg/configurator.h>
 
+#include "api/modules/capture.h"
 #include "acio/acio.h"
 #include "acio/icca/icca.h"
 #include "api/controller.h"
@@ -813,6 +814,7 @@ int main_implementation(int argc, char *argv[]) {
     if (options[launcher::Options::AdapterSubnet].is_active()) {
         NETWORK_SUBNET = options[launcher::Options::AdapterSubnet].value_text();
     }
+
     if (options[launcher::Options::APITCPPort].is_active()) {
         api_enable = true;
         api_port = options[launcher::Options::APITCPPort].value_uint32();
@@ -835,6 +837,13 @@ int main_implementation(int argc, char *argv[]) {
     if (options[launcher::Options::APIDebugMode].value_bool()) {
         api_debug = true;
     }
+    if (options[launcher::Options::APIScreenMirrorQuality].is_active()) {
+        api::modules::CAPTURE_QUALITY = options[launcher::Options::APIScreenMirrorQuality].value_uint32();
+    }
+    if (options[launcher::Options::APIScreenMirrorDivide].is_active()) {
+        api::modules::CAPTURE_DIVIDE = options[launcher::Options::APIScreenMirrorDivide].value_uint32();
+    }
+
     if (options[launcher::Options::DisableDebugHooks].value_bool()) {
         debughook::DEBUGHOOK_LOGGING = false;
     }

src/spice2x/launcher/options.cpp

@@ -1194,6 +1194,28 @@ static const std::vector<OptionDefinition> OPTION_DEFINITIONS = {
         .type = OptionType::Bool,
         .category = "API (Dev)",
     },
+    {
+        // APIScreenMirrorQuality
+        .title = "API Screen Mirror Quality Override",
+        .name = "apiscreenq",
+        .desc = "JPEG compression level of mirrored images, overriding any client request. "
+            "Value must be between 0 (poor quality) and 100 (best quality), inclusive. Default: 70",
+        .type = OptionType::Integer,
+        .setting_name = "(0-100)",
+        .category = "SpiceCompanion and API",
+    },
+    {
+        // APIScreenMirrorDivide
+        .title = "API Screen Mirror Divide Override",
+        .name = "apiscreendiv",
+        .desc = "Divide value of mirrored images, overriding any client request. "
+            "Divide of 1 means send every pixel, 2 means every other pixel, 3 means every third pixel, and so on; "
+            "increasing the value drastically reduces transfer size at the cost of image quality. "
+            "Value must be 1 or greater. Default: 1",
+        .type = OptionType::Integer,
+        .setting_name = "1",
+        .category = "SpiceCompanion and API",
+    },
     {
         .title = "Enable All IO Modules",
         .name = "io",

src/spice2x/launcher/options.h

@@ -136,6 +136,8 @@ namespace launcher {
             APISerialBaud,
             APIPretty,
             APIDebugMode,
+            APIScreenMirrorQuality,
+            APIScreenMirrorDivide,
             EnableAllIOModules,
             EnableACIOModule,
             EnableICCAModule,