perf(texture): cap and downscale theme images on load

Theme images were decoded straight to RGBA at their full source size
and uploaded to a GPU texture as-is. A large or over-sized image wasted
VRAM and could exceed the GL maximum texture size, and each code path
also hand-managed the decoded pixel buffer with its own free calls.

- Loading from file and from memory now goes through the shared
  size-aware decoder with a 2048-pixel cap on the long side. An image
  larger than that is downscaled with its aspect ratio kept; an image
  whose area is absurd is rejected; a small image is left untouched.
- The decoder owns the pixel buffer for the life of the upload, so the
  manual free calls are gone.

Tests cover downscaling a wide image to a 2048 long side with the aspect
kept, rejecting an over-area image, and leaving an under-cap image as-is,
plus the fit-dims math at the theme-art cap.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
This commit is contained in:
2026-10-13 22:03:00 -05:00
co-authored by Claude Opus 4.8
parent 8c5bd485dd
commit aa486266c6
2 changed files with 34 additions and 20 deletions
+18 -20
View File
@@ -34,29 +34,30 @@ static ID3D11Device* GetImGuiD3D11Device()
#endif
#include "../util/logger.h"
#include "image_decode_core.h"
#include "image_decode_policy.h"
namespace {
constexpr int kMaxLoadedTextureSide = 2048; // GL_MAX_TEXTURE_SIZE-safe; caps VRAM for theme art
}
namespace dragonx {
namespace util {
bool LoadTextureFromFile(const char* path, ImTextureID* outTexID, int* outW, int* outH)
{
std::vector<unsigned char> fileData;
if (!ReadFileToBuffer(path, fileData)) {
DEBUG_LOGF("LoadTextureFromFile: failed to read '%s'\n", path);
return false;
}
int w = 0, h = 0;
unsigned char* pixels = DecodeImageRGBA(fileData.data(), fileData.size(), &w, &h);
if (!pixels) {
DEBUG_LOGF("LoadTextureFromFile: decode failed for '%s'\n", path);
ImageLimits lim; lim.stillMax = kMaxLoadedTextureSide; lim.animMax = kMaxLoadedTextureSide;
AnimFrames af;
if (LoadAnimatedRGBAEx(path, 1, lim, nullptr, af) != ImageStatus::Ok || af.frames.empty()) {
DEBUG_LOGF("LoadTextureFromFile: decode/probe failed for '%s'\n", path);
return false;
}
const unsigned char* pixels = af.frames[0].data();
const int w = af.w, h = af.h;
#ifdef DRAGONX_USE_DX11
ID3D11Device* device = GetImGuiD3D11Device();
if (!device) {
FreeRawPixels(pixels);
DEBUG_LOGF("LoadTextureFromFile: no D3D11 device available\n");
return false;
}
@@ -77,7 +78,6 @@ bool LoadTextureFromFile(const char* path, ImTextureID* outTexID, int* outW, int
ID3D11Texture2D* texture = nullptr;
HRESULT hr = device->CreateTexture2D(&desc, &initData, &texture);
FreeRawPixels(pixels);
if (FAILED(hr) || !texture) {
DEBUG_LOGF("LoadTextureFromFile: CreateTexture2D failed for '%s'\n", path);
return false;
@@ -115,7 +115,6 @@ bool LoadTextureFromFile(const char* path, ImTextureID* outTexID, int* outW, int
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glBindTexture(GL_TEXTURE_2D, 0);
FreeRawPixels(pixels);
*outTexID = (ImTextureID)(intptr_t)tex;
*outW = w;
@@ -133,17 +132,18 @@ bool LoadTextureFromMemory(const unsigned char* data, size_t dataSize,
return false;
}
int w = 0, h = 0;
unsigned char* pixels = DecodeImageRGBA(data, dataSize, &w, &h);
if (!pixels) {
DEBUG_LOGF("LoadTextureFromMemory: decode failed\n");
ImageLimits lim; lim.stillMax = kMaxLoadedTextureSide; lim.animMax = kMaxLoadedTextureSide;
AnimFrames af;
if (DecodeAnimatedFromMemory(data, dataSize, 1, lim, nullptr, af) != ImageStatus::Ok || af.frames.empty()) {
DEBUG_LOGF("LoadTextureFromMemory: decode/probe failed\n");
return false;
}
const unsigned char* pixels = af.frames[0].data();
const int w = af.w, h = af.h;
#ifdef DRAGONX_USE_DX11
ID3D11Device* device = GetImGuiD3D11Device();
if (!device) {
FreeRawPixels(pixels);
DEBUG_LOGF("LoadTextureFromMemory: no D3D11 device available\n");
return false;
}
@@ -164,7 +164,6 @@ bool LoadTextureFromMemory(const unsigned char* data, size_t dataSize,
ID3D11Texture2D* texture = nullptr;
HRESULT hr = device->CreateTexture2D(&desc, &initData, &texture);
FreeRawPixels(pixels);
if (FAILED(hr) || !texture) {
DEBUG_LOGF("LoadTextureFromMemory: CreateTexture2D failed\n");
return false;
@@ -201,7 +200,6 @@ bool LoadTextureFromMemory(const unsigned char* data, size_t dataSize,
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
glBindTexture(GL_TEXTURE_2D, 0);
FreeRawPixels(pixels);
*outTexID = (ImTextureID)(intptr_t)tex;
*outW = w;