isle-portable/miniwin/src/d3drm/backends/software/renderer.cpp
2025-06-12 21:37:51 +02:00

661 lines
18 KiB
C++

#include "d3drmrenderer.h"
#include "d3drmrenderer_software.h"
#include "ddsurface_impl.h"
#include "mathutils.h"
#include "meshutils.h"
#include "miniwin.h"
#include <SDL3/SDL.h>
#include <algorithm>
#include <cmath>
#include <cstring>
#include <limits>
Direct3DRMSoftwareRenderer::Direct3DRMSoftwareRenderer(DWORD width, DWORD height) : m_width(width), m_height(height)
{
m_zBuffer.resize(m_width * m_height);
}
void Direct3DRMSoftwareRenderer::PushLights(const SceneLight* lights, size_t count)
{
m_lights.assign(lights, lights + count);
}
void Direct3DRMSoftwareRenderer::SetProjection(const D3DRMMATRIX4D& projection, D3DVALUE front, D3DVALUE back)
{
m_front = front;
m_back = back;
memcpy(m_projection, projection, sizeof(D3DRMMATRIX4D));
}
void Direct3DRMSoftwareRenderer::ClearZBuffer()
{
std::fill(m_zBuffer.begin(), m_zBuffer.end(), std::numeric_limits<float>::infinity());
}
void Direct3DRMSoftwareRenderer::ProjectVertex(const D3DRMVERTEX& v, D3DRMVECTOR4D& p) const
{
float px = m_projection[0][0] * v.position.x + m_projection[1][0] * v.position.y +
m_projection[2][0] * v.position.z + m_projection[3][0];
float py = m_projection[0][1] * v.position.x + m_projection[1][1] * v.position.y +
m_projection[2][1] * v.position.z + m_projection[3][1];
float pz = m_projection[0][2] * v.position.x + m_projection[1][2] * v.position.y +
m_projection[2][2] * v.position.z + m_projection[3][2];
float pw = m_projection[0][3] * v.position.x + m_projection[1][3] * v.position.y +
m_projection[2][3] * v.position.z + m_projection[3][3];
p.w = pw;
// Perspective divide
if (pw != 0.0f) {
float invW = 1.0f / pw;
px *= invW;
py *= invW;
pz *= invW;
}
// Map from NDC [-1,1] to screen coordinates
p.x = (px * 0.5f + 0.5f) * m_width;
p.y = (1.0f - (py * 0.5f + 0.5f)) * m_height;
p.z = pz;
}
D3DRMVERTEX SplitEdge(D3DRMVERTEX a, const D3DRMVERTEX& b, float plane)
{
float t = (plane - a.position.z) / (b.position.z - a.position.z);
a.position.x += t * (b.position.x - a.position.x);
a.position.y += t * (b.position.y - a.position.y);
a.position.z = plane;
a.texCoord.u += t * (b.texCoord.u - a.texCoord.u);
a.texCoord.v += t * (b.texCoord.v - a.texCoord.v);
a.normal.x += t * (b.normal.x - a.normal.x);
a.normal.y += t * (b.normal.y - a.normal.y);
a.normal.z += t * (b.normal.z - a.normal.z);
a.normal = Normalize(a.normal);
return a;
}
void Direct3DRMSoftwareRenderer::DrawTriangleClipped(const D3DRMVERTEX (&v)[3], const Appearance& appearance)
{
bool in0 = v[0].position.z >= m_front;
bool in1 = v[1].position.z >= m_front;
bool in2 = v[2].position.z >= m_front;
int insideCount = in0 + in1 + in2;
if (insideCount == 0) {
return;
}
if (insideCount == 3) {
DrawTriangleProjected(v[0], v[1], v[2], appearance);
}
else if (insideCount == 2) {
D3DRMVERTEX split;
if (!in0) {
split = SplitEdge(v[2], v[0], m_front);
DrawTriangleProjected(v[1], v[2], split, appearance);
DrawTriangleProjected(v[1], split, SplitEdge(v[1], v[0], m_front), appearance);
}
else if (!in1) {
split = SplitEdge(v[0], v[1], m_front);
DrawTriangleProjected(v[2], v[0], split, appearance);
DrawTriangleProjected(v[2], split, SplitEdge(v[2], v[1], m_front), appearance);
}
else {
split = SplitEdge(v[1], v[2], m_front);
DrawTriangleProjected(v[0], v[1], split, appearance);
DrawTriangleProjected(v[0], split, SplitEdge(v[0], v[2], m_front), appearance);
}
}
else if (in0) {
DrawTriangleProjected(v[0], SplitEdge(v[0], v[1], m_front), SplitEdge(v[0], v[2], m_front), appearance);
}
else if (in1) {
DrawTriangleProjected(SplitEdge(v[1], v[0], m_front), v[1], SplitEdge(v[1], v[2], m_front), appearance);
}
else {
DrawTriangleProjected(SplitEdge(v[2], v[0], m_front), SplitEdge(v[2], v[1], m_front), v[2], appearance);
}
}
void Direct3DRMSoftwareRenderer::BlendPixel(Uint8* pixelAddr, Uint8 r, Uint8 g, Uint8 b, Uint8 a)
{
Uint32 dstPixel = 0;
memcpy(&dstPixel, pixelAddr, m_bytesPerPixel);
Uint8 dstR, dstG, dstB, dstA;
SDL_GetRGBA(dstPixel, m_format, m_palette, &dstR, &dstG, &dstB, &dstA);
float alpha = a / 255.0f;
float invAlpha = 1.0f - alpha;
Uint8 outR = static_cast<Uint8>(r * alpha + dstR * invAlpha);
Uint8 outG = static_cast<Uint8>(g * alpha + dstG * invAlpha);
Uint8 outB = static_cast<Uint8>(b * alpha + dstB * invAlpha);
Uint8 outA = static_cast<Uint8>(a + dstA * invAlpha);
Uint32 blended = SDL_MapRGBA(m_format, m_palette, outR, outG, outB, outA);
switch (m_bytesPerPixel) {
case 1:
*pixelAddr = static_cast<Uint8>(blended);
break;
case 2:
*reinterpret_cast<Uint16*>(pixelAddr) = static_cast<Uint16>(blended);
break;
case 4:
*reinterpret_cast<Uint32*>(pixelAddr) = blended;
break;
}
}
SDL_Color Direct3DRMSoftwareRenderer::ApplyLighting(
const D3DVECTOR& position,
const D3DVECTOR& normal,
const Appearance& appearance
)
{
FColor specular = {0, 0, 0, 0};
FColor diffuse = {0, 0, 0, 0};
for (const auto& light : m_lights) {
FColor lightColor = light.color;
if (light.positional == 0.0f && light.directional == 0.0f) {
// Ambient light
diffuse.r += lightColor.r;
diffuse.g += lightColor.g;
diffuse.b += lightColor.b;
continue;
}
// TODO lightVec only has to be calculated once per frame for directional lights
D3DVECTOR lightVec;
if (light.directional == 1.0f) {
lightVec = {-light.direction.x, -light.direction.y, -light.direction.z};
}
else if (light.positional == 1.0f) {
lightVec = {light.position.x - position.x, light.position.y - position.y, light.position.z - position.z};
}
lightVec = Normalize(lightVec);
float dotNL = normal.x * lightVec.x + normal.y * lightVec.y + normal.z * lightVec.z;
if (dotNL > 0.0f) {
// Diffuse contribution
diffuse.r += dotNL * lightColor.r;
diffuse.g += dotNL * lightColor.g;
diffuse.b += dotNL * lightColor.b;
if (appearance.shininess != 0.0f) {
// Using dotNL ignores view angle, but this matches DirectX 5 behavior.
float spec = std::pow(dotNL, appearance.shininess * m_shininessFactor);
specular.r += spec * lightColor.r;
specular.g += spec * lightColor.g;
specular.b += spec * lightColor.b;
}
}
}
return SDL_Color{
static_cast<Uint8>(std::min(255.0f, diffuse.r * appearance.color.r + specular.r * 255.0f)),
static_cast<Uint8>(std::min(255.0f, diffuse.g * appearance.color.g + specular.g * 255.0f)),
static_cast<Uint8>(std::min(255.0f, diffuse.b * appearance.color.b + specular.b * 255.0f)),
appearance.color.a
};
}
struct VertexXY {
float x, y, z, w;
SDL_Color color;
float u_over_w, v_over_w;
float one_over_w;
};
VertexXY InterpolateVertex(float y, const VertexXY& v0, const VertexXY& v1)
{
float dy = v1.y - v0.y;
if (fabsf(dy) < 1e-6f) {
dy = 1e-6f;
}
float t = (y - v0.y) / dy;
VertexXY r;
r.x = v0.x + t * (v1.x - v0.x);
r.z = v0.z + t * (v1.z - v0.z);
r.w = v0.w + t * (v1.w - v0.w);
r.color.r = static_cast<Uint8>(v0.color.r + t * (v1.color.r - v0.color.r));
r.color.g = static_cast<Uint8>(v0.color.g + t * (v1.color.g - v0.color.g));
r.color.b = static_cast<Uint8>(v0.color.b + t * (v1.color.b - v0.color.b));
r.color.a = static_cast<Uint8>(v0.color.a + t * (v1.color.a - v0.color.a));
r.u_over_w = v0.u_over_w + t * (v1.u_over_w - v0.u_over_w);
r.v_over_w = v0.v_over_w + t * (v1.v_over_w - v0.v_over_w);
r.one_over_w = v0.one_over_w + t * (v1.one_over_w - v0.one_over_w);
return r;
}
void Direct3DRMSoftwareRenderer::DrawTriangleProjected(
const D3DRMVERTEX& v0,
const D3DRMVERTEX& v1,
const D3DRMVERTEX& v2,
const Appearance& appearance
)
{
D3DRMVECTOR4D p0, p1, p2;
ProjectVertex(v0, p0);
ProjectVertex(v1, p1);
ProjectVertex(v2, p2);
// Skip triangles outside the frustum
if ((p0.z < m_front && p1.z < m_front && p2.z < m_front) || (p0.z > m_back && p1.z > m_back && p2.z > m_back)) {
return;
}
// Skip offscreen triangles
if ((p0.x < 0 && p1.x < 0 && p2.x < 0) || (p0.x >= m_width && p1.x >= m_width && p2.x >= m_width) ||
(p0.y < 0 && p1.y < 0 && p2.y < 0) || (p0.y >= m_height && p1.y >= m_height && p2.y >= m_height)) {
return;
}
// Cull backfaces
if ((p2.x - p0.x) * (p1.y - p0.y) - (p2.y - p0.y) * (p1.x - p0.x) >= 0) {
return;
}
Uint8 r, g, b;
SDL_Color c0 = ApplyLighting(v0.position, v0.normal, appearance);
SDL_Color c1 = {}, c2 = {};
if (!appearance.flat) {
c1 = ApplyLighting(v1.position, v1.normal, appearance);
c2 = ApplyLighting(v2.position, v2.normal, appearance);
}
Uint32 textureId = appearance.textureId;
int texturePitch;
Uint8* texels = nullptr;
int texWidthScale;
int texHeightScale;
if (textureId != NO_TEXTURE_ID) {
SDL_Surface* texture = m_textures[textureId].cached;
if (texture) {
texturePitch = texture->pitch;
texels = static_cast<Uint8*>(texture->pixels);
texWidthScale = texture->w - 1;
texHeightScale = texture->h - 1;
}
}
Uint8* pixels = (Uint8*) DDBackBuffer->pixels;
int pitch = DDBackBuffer->pitch;
VertexXY verts[3] = {
{p0.x, p0.y, p0.z, p0.w, c0, v0.texCoord.u, v0.texCoord.v},
{p1.x, p1.y, p1.z, p1.w, c1, v1.texCoord.u, v1.texCoord.v},
{p2.x, p2.y, p2.z, p2.w, c2, v2.texCoord.u, v2.texCoord.v}
};
verts[0].u_over_w = v0.texCoord.u / p0.w;
verts[0].v_over_w = v0.texCoord.v / p0.w;
verts[0].one_over_w = 1.0f / p0.w;
verts[1].u_over_w = v1.texCoord.u / p1.w;
verts[1].v_over_w = v1.texCoord.v / p1.w;
verts[1].one_over_w = 1.0f / p1.w;
verts[2].u_over_w = v2.texCoord.u / p2.w;
verts[2].v_over_w = v2.texCoord.v / p2.w;
verts[2].one_over_w = 1.0f / p2.w;
// Sort verts
if (verts[0].y > verts[1].y) {
std::swap(verts[0], verts[1]);
}
if (verts[1].y > verts[2].y) {
std::swap(verts[1], verts[2]);
}
if (verts[0].y > verts[1].y) {
std::swap(verts[0], verts[1]);
}
int minY = std::max(0, (int) std::ceil(verts[0].y));
int maxY = std::min((int) m_height - 1, (int) std::floor(verts[2].y));
for (int y = minY; y <= maxY; ++y) {
VertexXY left, right;
if (y < verts[1].y) {
left = InterpolateVertex(y, verts[0], verts[1]);
right = InterpolateVertex(y, verts[0], verts[2]);
}
else {
left = InterpolateVertex(y, verts[1], verts[2]);
right = InterpolateVertex(y, verts[0], verts[2]);
}
if (left.x > right.x) {
std::swap(left, right);
}
int startX = std::max(0, (int) std::ceil(left.x));
int endX = std::min((int) m_width - 1, (int) std::floor(right.x));
float span = right.x - left.x;
if (span == 0.0f) {
continue;
}
for (int x = startX; x <= endX; ++x) {
float t = (x - left.x) / span;
float z = left.z + t * (right.z - left.z);
int zidx = y * m_width + x;
float& zref = m_zBuffer[zidx];
if (z >= zref) {
continue;
}
Uint8 r, g, b;
if (appearance.flat) {
r = c0.r;
g = c0.g;
b = c0.b;
}
else {
r = static_cast<Uint8>(left.color.r + t * (right.color.r - left.color.r));
g = static_cast<Uint8>(left.color.g + t * (right.color.g - left.color.g));
b = static_cast<Uint8>(left.color.b + t * (right.color.b - left.color.b));
}
Uint8* pixelAddr = pixels + y * pitch + x * m_bytesPerPixel;
if (appearance.color.a == 255) {
zref = z;
if (texels) {
// Perspective correct interpolate texture coords
float one_over_w = left.one_over_w + t * (right.one_over_w - left.one_over_w);
float u_over_w = left.u_over_w + t * (right.u_over_w - left.u_over_w);
float v_over_w = left.v_over_w + t * (right.v_over_w - left.v_over_w);
float inv_w = 1.0f / one_over_w;
float u = u_over_w * inv_w;
float v = v_over_w * inv_w;
// Tile textures
u -= std::floor(u);
v -= std::floor(v);
int texX = static_cast<int>(u * texWidthScale);
int texY = static_cast<int>(v * texHeightScale);
Uint8* texelAddr = texels + texY * texturePitch + texX * m_bytesPerPixel;
Uint32 texelColor;
switch (m_bytesPerPixel) {
case 1:
texelColor = *texelAddr;
break;
case 2:
texelColor = *(Uint16*) texelAddr;
break;
case 4:
texelColor = *(Uint32*) texelAddr;
break;
}
Uint8 tr, tg, tb, ta;
SDL_GetRGBA(texelColor, m_format, m_palette, &tr, &tg, &tb, &ta);
// Multiply vertex color by texel color
r = (r * tr + 127) / 255;
g = (g * tg + 127) / 255;
b = (b * tb + 127) / 255;
}
Uint32 finalColor = SDL_MapRGBA(m_format, m_palette, r, g, b, 255);
switch (m_bytesPerPixel) {
case 1:
*pixelAddr = static_cast<Uint8>(finalColor);
break;
case 2:
*reinterpret_cast<Uint16*>(pixelAddr) = static_cast<Uint16>(finalColor);
break;
case 4:
*reinterpret_cast<Uint32*>(pixelAddr) = finalColor;
break;
}
}
else {
// Transparent alpha blending with vertex alpha
BlendPixel(pixelAddr, r, g, b, appearance.color.a);
}
}
}
}
struct CacheDestroyContext {
Direct3DRMSoftwareRenderer* renderer;
Uint32 id;
};
void Direct3DRMSoftwareRenderer::AddTextureDestroyCallback(Uint32 id, IDirect3DRMTexture* texture)
{
auto* ctx = new CacheDestroyContext{this, id};
texture->AddDestroyCallback(
[](IDirect3DRMObject* obj, void* arg) {
auto* ctx = static_cast<CacheDestroyContext*>(arg);
auto& cacheEntry = ctx->renderer->m_textures[ctx->id];
if (cacheEntry.cached) {
SDL_UnlockSurface(cacheEntry.cached);
SDL_DestroySurface(cacheEntry.cached);
cacheEntry.cached = nullptr;
cacheEntry.texture = nullptr;
}
delete ctx;
},
ctx
);
}
Uint32 Direct3DRMSoftwareRenderer::GetTextureId(IDirect3DRMTexture* iTexture)
{
auto texture = static_cast<Direct3DRMTextureImpl*>(iTexture);
auto surface = static_cast<DirectDrawSurfaceImpl*>(texture->m_surface);
// Check if already mapped
for (Uint32 i = 0; i < m_textures.size(); ++i) {
auto& texRef = m_textures[i];
if (texRef.texture == texture) {
if (texRef.version != texture->m_version) {
// Update animated textures
SDL_DestroySurface(texRef.cached);
texRef.cached = SDL_ConvertSurface(surface->m_surface, DDBackBuffer->format);
SDL_LockSurface(texRef.cached);
texRef.version = texture->m_version;
}
return i;
}
}
SDL_Surface* convertedRender = SDL_ConvertSurface(surface->m_surface, DDBackBuffer->format);
SDL_LockSurface(convertedRender);
// Reuse freed slot
for (Uint32 i = 0; i < m_textures.size(); ++i) {
auto& texRef = m_textures[i];
if (!texRef.texture) {
texRef = {texture, texture->m_version, convertedRender};
AddTextureDestroyCallback(i, texture);
return i;
}
}
// Append new
m_textures.push_back({texture, texture->m_version, convertedRender});
AddTextureDestroyCallback(static_cast<Uint32>(m_textures.size() - 1), texture);
return static_cast<Uint32>(m_textures.size() - 1);
}
MeshCache UploadMesh(const MeshGroup& meshGroup)
{
MeshCache cache{&meshGroup, meshGroup.version};
cache.flat = meshGroup.quality == D3DRMRENDER_FLAT || meshGroup.quality == D3DRMRENDER_UNLITFLAT;
std::vector<D3DRMVERTEX> vertices;
if (cache.flat) {
FlattenSurfaces(
meshGroup.vertices.data(),
meshGroup.vertices.size(),
meshGroup.indices.data(),
meshGroup.indices.size(),
meshGroup.texture != nullptr,
cache.vertices,
cache.indices
);
}
else {
cache.vertices.assign(meshGroup.vertices.begin(), meshGroup.vertices.end());
cache.indices.assign(meshGroup.indices.begin(), meshGroup.indices.end());
}
return cache;
}
void Direct3DRMSoftwareRenderer::AddMeshDestroyCallback(Uint32 id, IDirect3DRMMesh* mesh)
{
auto* ctx = new CacheDestroyContext{this, id};
mesh->AddDestroyCallback(
[](IDirect3DRMObject* obj, void* arg) {
auto* ctx = static_cast<CacheDestroyContext*>(arg);
auto& cacheEntry = ctx->renderer->m_meshs[ctx->id];
if (cacheEntry.meshGroup) {
cacheEntry.meshGroup = nullptr;
cacheEntry.vertices.clear();
cacheEntry.indices.clear();
}
delete ctx;
},
ctx
);
}
Uint32 Direct3DRMSoftwareRenderer::GetMeshId(IDirect3DRMMesh* mesh, const MeshGroup* meshGroup)
{
for (Uint32 i = 0; i < m_meshs.size(); ++i) {
auto& cache = m_meshs[i];
if (cache.meshGroup == meshGroup) {
if (cache.version != meshGroup->version) {
cache = std::move(UploadMesh(*meshGroup));
}
return i;
}
}
auto newCache = UploadMesh(*meshGroup);
for (Uint32 i = 0; i < m_meshs.size(); ++i) {
auto& cache = m_meshs[i];
if (!cache.meshGroup) {
cache = std::move(newCache);
AddMeshDestroyCallback(i, mesh);
return i;
}
}
m_meshs.push_back(std::move(newCache));
AddMeshDestroyCallback((Uint32) (m_meshs.size() - 1), mesh);
return (Uint32) (m_meshs.size() - 1);
}
DWORD Direct3DRMSoftwareRenderer::GetWidth()
{
return m_width;
}
DWORD Direct3DRMSoftwareRenderer::GetHeight()
{
return m_height;
}
void Direct3DRMSoftwareRenderer::GetDesc(D3DDEVICEDESC* halDesc, D3DDEVICEDESC* helDesc)
{
memset(halDesc, 0, sizeof(D3DDEVICEDESC));
helDesc->dcmColorModel = D3DCOLORMODEL::RGB;
helDesc->dwFlags = D3DDD_DEVICEZBUFFERBITDEPTH;
helDesc->dwDeviceZBufferBitDepth = DDBD_32;
helDesc->dwDeviceRenderBitDepth = DDBD_8 | DDBD_16 | DDBD_24 | DDBD_32;
helDesc->dpcTriCaps.dwTextureCaps = D3DPTEXTURECAPS_PERSPECTIVE;
helDesc->dpcTriCaps.dwShadeCaps = D3DPSHADECAPS_ALPHAFLATBLEND;
helDesc->dpcTriCaps.dwTextureFilterCaps = D3DPTFILTERCAPS_LINEAR;
}
const char* Direct3DRMSoftwareRenderer::GetName()
{
return "Miniwin Emulation";
}
HRESULT Direct3DRMSoftwareRenderer::BeginFrame(const D3DRMMATRIX4D& viewMatrix)
{
if (!DDBackBuffer || !SDL_LockSurface(DDBackBuffer)) {
return DDERR_GENERIC;
}
ClearZBuffer();
memcpy(m_viewMatrix, viewMatrix, sizeof(D3DRMMATRIX4D));
m_format = SDL_GetPixelFormatDetails(DDBackBuffer->format);
m_palette = SDL_GetSurfacePalette(DDBackBuffer);
m_bytesPerPixel = m_format->bits_per_pixel / 8;
return DD_OK;
}
void Direct3DRMSoftwareRenderer::EnableTransparency()
{
}
void Direct3DRMSoftwareRenderer::SubmitDraw(
DWORD meshId,
const D3DRMMATRIX4D& worldMatrix,
const Matrix3x3& normalMatrix,
const Appearance& appearance
)
{
D3DRMMATRIX4D mvMatrix;
MultiplyMatrix(mvMatrix, worldMatrix, m_viewMatrix);
auto& mesh = m_meshs[meshId];
// Pre-transform all vertex positions and normals
std::vector<D3DRMVERTEX> transformedVerts(mesh.vertices.size());
for (size_t i = 0; i < mesh.vertices.size(); ++i) {
const D3DRMVERTEX& src = mesh.vertices[i];
D3DRMVERTEX& dst = transformedVerts[i];
dst.position = TransformPoint(src.position, mvMatrix);
// TODO defer normal transformation til lighting to allow culling first
dst.normal = Normalize(TransformNormal(src.normal, normalMatrix));
dst.texCoord = src.texCoord;
}
// Assemble triangles using index buffer
for (size_t i = 0; i + 2 < mesh.indices.size(); i += 3) {
DrawTriangleClipped(
{transformedVerts[mesh.indices[i]],
transformedVerts[mesh.indices[i + 1]],
transformedVerts[mesh.indices[i + 2]]},
appearance
);
}
}
HRESULT Direct3DRMSoftwareRenderer::FinalizeFrame()
{
SDL_UnlockSurface(DDBackBuffer);
return DD_OK;
}