Add naiive SSAA for primitive triangles only

src/DTRenderer.cpp

@@ -904,8 +904,9 @@ extern "C" void DTR_Update(PlatformRenderBuffer *const platformRenderBuffer,
 		// Init Assets
 		////////////////////////////////////////////////////////////////////////
 		DTRAsset_InitGlobalState();
+		const f32 FONT_SIZE = 14;
 		DTRAsset_LoadFontToBitmap(input->api, &memory->mainStack, tempStack, &state->font,
-		                          "Roboto-bold.ttf", DqnV2i_2i(256, 256), DqnV2i_2i(' ', '~'), 12);
+		                          "Roboto-bold.ttf", DqnV2i_2i(256, 256), DqnV2i_2i(' ', '~'), FONT_SIZE);
 		DTRAsset_LoadBitmap(input->api, assetStack,
 		                    tempStack, &state->bitmap, "tree00.bmp");
 
@@ -959,7 +960,7 @@ extern "C" void DTR_Update(PlatformRenderBuffer *const platformRenderBuffer,
 	////////////////////////////////////////////////////////////////////////////
 	// Update and Render
 	////////////////////////////////////////////////////////////////////////////
-	DTRRender_Clear(&renderBuffer, DqnV3_3f(0.5f, 0.0f, 1.0f));
+	DTRRender_Clear(&renderBuffer, DqnV3_3f(0.0f, 0.0f, 0.0f));
 
 #if 1
 	DqnV4 colorRed    = DqnV4_4f(0.8f, 0, 0, 1);
@@ -980,14 +981,17 @@ extern "C" void DTR_Update(PlatformRenderBuffer *const platformRenderBuffer,
 		DqnV3 t4[3] = {DqnV3_3i(100, 150, 0), DqnV3_3i(200, 150, 0), DqnV3_3i(200, 250, 0)};
 		DqnV3 t5[3] = {DqnV3_3i(300, 150, 0), DqnV3_3i(201, 150, 0), DqnV3_3i(200, 250, 0)};
 
-		DTRRenderTransform rotatingXform = DTRRender_DefaultTriangleTransform();
-		rotatingXform.rotation           = rotation;
-
 		if (1)
 		{
+
+			DTRRenderTransform rotatingXform = DTRRender_DefaultTriangleTransform();
+			rotatingXform.rotation           = rotation * 0.25f;
+
 			DTRDebug_BeginCycleCount("DTR_Update_RenderPrimitiveTriangles",
 			                         DTRDebugCycleCount_DTR_Update_RenderPrimitiveTriangles);
 
+			DTRRenderTransform scaleXform = DTRRender_DefaultTriangleTransform();
+			scaleXform.scale              = DqnV3_1f(5);
 			DTRRender_Triangle(&renderBuffer, t0[0], t0[1], t0[2], colorRed);
 			DTRRender_Triangle(&renderBuffer, t1[0], t1[1], t1[2], colorRed);
 			DTRRender_Triangle(&renderBuffer, t3[0], t3[1], t3[2], colorRed, rotatingXform);
@@ -997,7 +1001,7 @@ extern "C" void DTR_Update(PlatformRenderBuffer *const platformRenderBuffer,
 			DTRDebug_EndCycleCount(DTRDebugCycleCount_DTR_Update_RenderPrimitiveTriangles);
 		}
 
-		if (1)
+		if (0)
 		{
 			LOCAL_PERSIST bool runTinyRendererOnce = false;
 			if (1 && runTinyRendererOnce)
@@ -1016,7 +1020,7 @@ extern "C" void DTR_Update(PlatformRenderBuffer *const platformRenderBuffer,
 			DqnV3 modelP          = DqnV3_3f(0, 0, 0);
 
 			LOCAL_PERSIST f32 modelRotation = 0;
-			modelRotation += (input->deltaForFrame * 20.0f);
+			modelRotation += (input->deltaForFrame * 80.0f);
 			DqnV3 axis = DqnV3_3f(0, 1, 0);
 
 			DTRRenderTransform transform = DTRRender_DefaultTransform();

src/DTRendererDebug.cpp

@@ -216,7 +216,7 @@ void DTRDebug_Update(DTRState *const state,
 		debug->renderBuffer = renderBuffer;
 		debug->input        = input;
 		debug->font         = &state->font;
-		debug->displayColor = DqnV4_4f(1, 1, 1, 1);
+		debug->displayColor = DqnV4_4f(1, 1, 1, 0.85f);
 		if (debug->font->bitmap && debug->renderBuffer)
 		{
 			debug->displayYOffset = -(i32)(state->font.sizeInPt + 0.5f);

src/DTRendererRender.cpp

@@ -1146,10 +1146,45 @@ FILE_SCOPE void SlowTriangle(DTRRenderBuffer *const renderBuffer, const DqnV3 p1
 
 		for (i32 bufferX = min.x; bufferX < max.x; bufferX++)
 		{
-			if (signedArea1 >= 0 && signedArea2 >= 0 && signedArea3 >= 0)
+			// TODO(doyle): Use signedArea1/2/3 and subsample increments from the signedAreaDeltas
+			const u32 NUM_SAMPLES_ALONG_AXIS = 2;
+			const u32 SAMPLES_PER_PIXEL      = DQN_SQUARED(NUM_SAMPLES_ALONG_AXIS);
+			DQN_ASSERT((NUM_SAMPLES_ALONG_AXIS & 1) == 0);
+
+			const f32 SAMPLE_COVERAGE_INCREMENT = 1 / (f32)SAMPLES_PER_PIXEL;
+			const f32 SAMPLE_XY_INCREMENT       = 1 / (f32)NUM_SAMPLES_ALONG_AXIS;
+
+			f32 subsampleCoverage = 0;
+			for (i32 sampleY = 0; sampleY < NUM_SAMPLES_ALONG_AXIS; sampleY++)
+			{
+				for (i32 sampleX = 0; sampleX < NUM_SAMPLES_ALONG_AXIS; sampleX++)
+				{
+					f32 granularX = sampleX * SAMPLE_XY_INCREMENT;
+					f32 granularY = sampleY * SAMPLE_XY_INCREMENT;
+
+					DqnV2 subsample = DqnV2_2f((f32)bufferX + granularX, (f32)bufferY + granularY);
+
+					f32 subsampleSignedArea1 = Triangle2TimesSignedArea(p2.xy, p3.xy, subsample);
+					f32 subsampleSignedArea2 = Triangle2TimesSignedArea(p3.xy, p1.xy, subsample);
+					f32 subsampleSignedArea3 = Triangle2TimesSignedArea(p1.xy, p2.xy, subsample);
+
+					if (subsampleSignedArea1 >= 0 && subsampleSignedArea2 >= 0 &&
+					    subsampleSignedArea3 >= 0)
+					{
+						subsampleCoverage += SAMPLE_COVERAGE_INCREMENT;
+					}
+				}
+			}
+			DQN_ASSERT(subsampleCoverage >= 0.0f && subsampleCoverage <= 1.0f);
+
+			// TODO(doyle): Crashes when using meshes, since we are now sampling
+			// outside the actual specified mesh, (i.e. pixels just before it
+			// for SSAA) the barycentric coordinates sample outside the texture.
+			// Naiive workarounds will cause color artifacts or gaps in rendered
+			// meshes.
+			if (subsampleCoverage > 0)
 			{
 				DEBUG_SLOW_AUTO_CHOOSE_BEGIN_CYCLE_COUNT(Triangle_RasterisePixel);
-				f32 barycentricA = signedArea1 * invSignedAreaParallelogram;
 				f32 barycentricB = signedArea2 * invSignedAreaParallelogram;
 				f32 barycentricC = signedArea3 * invSignedAreaParallelogram;
 
@@ -1158,18 +1193,28 @@ FILE_SCOPE void SlowTriangle(DTRRenderBuffer *const renderBuffer, const DqnV3 p1
 				f32 currZValue   = renderBuffer->zBuffer[zBufferIndex];
 				DQN_ASSERT(zBufferIndex < (renderBuffer->width * renderBuffer->height));
 
-				if (pixelZValue > currZValue)
+				if (pixelZValue >= currZValue)
 				{
 					renderBuffer->zBuffer[zBufferIndex] = pixelZValue;
 					DqnV4 finalColor                    = color;
+					DQN_ASSERT(finalColor.x >= 0);
+
+					// NOTE: Multiply everything by the coverage alpha since
+					// colors need to be premultiplied alpha.
+					finalColor *= subsampleCoverage;
+					DQN_ASSERT(finalColor.x >= 0);
 
 					if (!ignoreLight)
 					{
-						DqnV3 light = (p1Light * barycentricA) + (p2Light * barycentricB) +
+						f32 barycentricA = signedArea1 * invSignedAreaParallelogram;
+						DqnV3 light      = (p1Light * barycentricA) + (p2Light * barycentricB) +
 						              (p3Light * barycentricC);
 						finalColor.rgb *= light;
+						DQN_ASSERT(finalColor.x >= 0);
 					}
 
+					DQN_ASSERT(finalColor.x >= 0);
+
 					if (texture)
 					{
 						DqnV2 uv = uv1 + (uv2SubUv1 * barycentricB) + (uv3SubUv1 * barycentricC);
@@ -1200,9 +1245,13 @@ FILE_SCOPE void SlowTriangle(DTRRenderBuffer *const renderBuffer, const DqnV3 p1
 						color1 *= INV_255;
 						color1 = DTRRender_SRGB1ToLinearSpaceV4(color1);
 						finalColor *= color1;
+
+						DQN_ASSERT(finalColor.x >= 0);
 					}
 
 					SetPixel(renderBuffer, bufferX, bufferY, finalColor, ColorSpace_Linear);
+
+					int breakhere = 5;
 				}
 				DEBUG_SLOW_AUTO_CHOOSE_END_CYCLE_COUNT(Triangle_RasterisePixel);
 			}
@@ -1306,7 +1355,7 @@ FILE_SCOPE void TexturedTriangleInternal(DTRRenderBuffer *const renderBuffer,
 	////////////////////////////////////////////////////////////////////////////
 	// SIMD/Slow Path
 	////////////////////////////////////////////////////////////////////////////
-	if (globalDTRPlatformFlags.canUseSSE2)
+	if (globalDTRPlatformFlags.canUseSSE2 && 0)
 	{
 		SIMDTriangle(renderBuffer, p1, p2, p3, uv1, uv2, uv3, lightIntensity1, lightIntensity2,
 		             lightIntensity3, ignoreLight, texture, color, min, max);

src/build.bat

@@ -39,7 +39,7 @@ REM wd4100 unused argument parameters
 REM wd4201 nonstandard extension used: nameless struct/union
 REM wd4189 local variable is initialised but not referenced
 REM wd4505 unreferenced local function not used will be removed
-set CompileFlags=-EHsc -GR- -Oi -MT -Z7 -W4 -wd4100 -wd4201 -wd4189 -wd4505 -O2 -FAsc /I..\src\external\
+set CompileFlags=-EHsc -GR- -Oi -MT -Z7 -W4 -wd4100 -wd4201 -wd4189 -wd4505 -Od -FAsc /I..\src\external\
 set DLLFlags=/Fm%ProjectName% /Fo%ProjectName% /Fa%ProjectName% /Fe%ProjectName%
 set Win32Flags=/FmWin32DTRenderer /FeWin32DTRenderer