Rendering player and tiles now works.

src/graphics/GameRenderer.cpp

@@ -0,0 +1,146 @@
+/*
+ * GameRenderer.cpp
+ *
+ *  Created on: Nov 13, 2016
+ *      Author: tibi
+ */
+#include <GameState.h>
+#include <graphics/GameRenderer.h>
+#include <math/GameMath.h>
+#include <resources/Resources.h>
+
+namespace farmlands {
+namespace graphics {
+
+GameRenderer::GameRenderer()
+	: m_gameState(nullptr)
+{
+}
+
+GameRenderer::~GameRenderer()
+{
+}
+
+void GameRenderer::initialize(GameState* gameState)
+{
+	m_gameState = gameState;
+}
+
+void GameRenderer::render()
+{
+	prepareRender();
+	renderTileLayers();
+	renderPlayer();
+}
+
+void GameRenderer::prepareRender()
+{
+	m_cellW = m_gameState->currentLevel->m_cellWidth * m_gameState->camera.scale;
+	m_cellH = m_gameState->currentLevel->m_cellHeight * m_gameState->camera.scale;
+}
+
+void GameRenderer::renderTileLayers()
+{
+	// Compute how many cells fit on the screen
+	float cellsOnScreenX = m_gameState->viewport.width / m_cellW;
+	float cellsOnScreenY = m_gameState->viewport.height / m_cellH;
+
+	int minCellX = floorf(m_gameState->camera.posX - cellsOnScreenX / 2);
+	int minCellY = floorf(m_gameState->camera.posY - cellsOnScreenY / 2);
+	int maxCellX = ceilf(m_gameState->camera.posX + cellsOnScreenX / 2);
+	int maxCellY = ceilf(m_gameState->camera.posY + cellsOnScreenY / 2);
+
+	// Clamp cell positions
+	minCellX = clamp(minCellX, 0, (int)m_gameState->currentLevel->columnCount() - 1);
+	minCellY = clamp(minCellY, 0, (int)m_gameState->currentLevel->rowCount() - 1);
+	maxCellX = clamp(maxCellX, 0, (int)m_gameState->currentLevel->columnCount() - 1);
+	maxCellY = clamp(maxCellY, 0, (int)m_gameState->currentLevel->rowCount() - 1);
+
+	// Draw each layer
+	for (size_t i = 0; i < m_gameState->currentLevel->layerCount(); i++)
+	{
+		int textureId = m_gameState->currentLevel->texture(i);
+
+		// Render only visible tiles
+		for (int y = minCellY; y <= maxCellY; y++)
+			for (int x = minCellX; x <= maxCellX; x++)
+			{
+				int cellId = m_gameState->currentLevel->cell(i, y, x);
+
+				// Obtain texture
+				int texWidth, texHeight;
+				SDL_Texture* texture = m_gameState->resManager.texture(textureId);
+				SDL_QueryTexture(texture, NULL, NULL, &texWidth, &texHeight);
+
+				// Compute texture coordinates
+				int cellCol = (cellId * m_gameState->currentLevel->m_cellWidth) % texWidth;
+				int cellRow = ((cellId * m_gameState->currentLevel->m_cellWidth) / texWidth) * m_gameState->currentLevel->m_cellHeight;
+
+				// Calculate source position
+				SDL_Rect src =
+				{
+					cellCol,
+					cellRow,
+					(int) m_gameState->currentLevel->m_cellWidth,
+					(int) m_gameState->currentLevel->m_cellHeight
+				};
+
+				// Calculate destination position
+				SDL_Rect dest =
+				{
+					(int) xToScreen(x),
+					(int) yToScreen(y),
+					(int) ceilf(m_cellW),
+					(int) ceilf(m_cellH)
+				};
+
+				// Blit
+				SDL_RenderCopy(m_gameState->sdlRenderer.internalRenderer(), texture, &src, &dest);
+			}
+	}
+}
+
+void GameRenderer::renderPlayer()
+{
+	float posX = xToScreen(m_gameState->player.posX);
+	float posY = yToScreen(m_gameState->player.posY);
+
+	// Obtain texture
+	int texWidth, texHeight;
+	SDL_Texture* playerTexture = m_gameState->resManager.texture(resources::R::Player::Default);
+	SDL_QueryTexture(playerTexture, NULL, NULL, &texWidth, &texHeight);
+
+	// Draw using bottom center of texture as anchor point
+	SDL_Rect dest =
+	{
+		(int) (posX - texWidth * m_gameState->camera.scale / 2),
+		(int) (posY - texHeight * m_gameState->camera.scale),
+		(int) (texWidth * m_gameState->camera.scale),
+		(int) (texHeight * m_gameState->camera.scale),
+	};
+
+	SDL_RenderCopy(m_gameState->sdlRenderer.internalRenderer(), playerTexture, NULL, &dest);
+}
+
+float GameRenderer::xToWorld(float x)
+{
+	return (x - m_gameState->viewport.width / 2) / m_cellW + m_gameState->camera.posX;
+}
+
+float GameRenderer::yToWorld(float y)
+{
+	return (y - m_gameState->viewport.height / 2) / m_cellH + m_gameState->camera.posY;
+}
+
+float GameRenderer::xToScreen(float x)
+{
+	return (x - m_gameState->camera.posX) * m_cellW + m_gameState->viewport.width / 2;
+}
+
+float GameRenderer::yToScreen(float y)
+{
+	return (y - m_gameState->camera.posY) * m_cellH + m_gameState->viewport.height / 2;
+}
+
+} /* namespace graphics */
+} /* namespace farmlands */