cmake/targets/linux.cmake

@@ -29,6 +29,7 @@ target_compile_definitions(${DUSK_LIBRARY_TARGET_NAME} PUBLIC
   DUSK_SDL2
   DUSK_OPENGL
   DUSK_LINUX
+  DUSK_OPENGL_LEGACY
   DUSK_DISPLAY_SIZE_DYNAMIC
   DUSK_DISPLAY_WIDTH_DEFAULT=640
   DUSK_DISPLAY_HEIGHT_DEFAULT=480

src/dusk/display/shader/shader.c

@@ -23,7 +23,7 @@ errorret_t shaderBind(shader_t *shader) {
 errorret_t shaderSetMatrix(
   shader_t *shader,
   const char_t *name,
-  const mat4 matrix
+  mat4 matrix
 ) {
   assertNotNull(shader, "Shader cannot be null");
   assertStrLenMin(name, 1, "Uniform name cannot be empty");

src/dusk/display/shader/shader.h

@@ -54,7 +54,7 @@ errorret_t shaderBind(shader_t *shader);
 errorret_t shaderSetMatrix(
   shader_t *shader,
   const char_t *name,
-  const mat4 matrix
+  mat4 matrix
 );
 
 /**

src/duskgl/display/displaygl.c

@@ -8,8 +8,6 @@
 #include "displaygl.h"
 
 errorret_t displayOpenGLInit(void) {
-  
-
   glDisable(GL_CULL_FACE);
   // glDisable(GL_LIGHTING);// PSP defaults this on?
   // glShadeModel(GL_SMOOTH); // Fixes color on PSP?
@@ -26,10 +24,5 @@ errorret_t displayOpenGLInit(void) {
   glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
   errorChain(errorGLCheck());
 
-  // glEnableClientState(GL_COLOR_ARRAY);// To confirm: every frame on PSP?
-  // glEnableClientState(GL_TEXTURE_COORD_ARRAY);
-  // glEnableClientState(GL_VERTEX_ARRAY);
-  // errorChain(errorGLCheck());
-
   errorOk();
 }

src/duskgl/display/mesh/meshgl.c

@@ -8,6 +8,7 @@
 #include "display/mesh/mesh.h"
 #include "assert/assertgl.h"
 #include "error/errorgl.h"
+#include "display/shader/shadergl.h"
 
 errorret_t meshInitGL(
   meshgl_t *mesh,
@@ -25,6 +26,10 @@ errorret_t meshInitGL(
 
   #ifdef DUSK_OPENGL_LEGACY
     // Nothing needed.
+    glEnableClientState(GL_COLOR_ARRAY);
+    glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+    glEnableClientState(GL_VERTEX_ARRAY);
+    errorChain(errorGLCheck());
   #else
     // Generate Vertex Buffer Object
     glGenBuffers(1, &mesh->vboId);
@@ -143,6 +148,11 @@ errorret_t meshDrawGL(
       (const GLvoid*)&mesh->vertices[offset].pos
     );
 
+    // Shader may have model matrix here
+    #ifdef DUSK_OPENGL_LEGACY
+      errorChain(shaderLegacyMatrixUpdate());
+    #endif
+    
     glDrawArrays(mesh->primitiveType, offset, count);
     errorChain(errorGLCheck());
   #else

src/duskgl/display/shader/shadergl.c

@@ -7,7 +7,13 @@
 
 #include "shadergl.h"
 #include "util/memory.h"
+#include "util/string.h"
 #include "assert/assertgl.h"
+#include "display/shader/shaderunlit.h"
+
+#ifdef DUSK_OPENGL_LEGACY
+  shaderlegacygl_t SHADER_LEGACY = { 0 };
+#endif
 
 errorret_t shaderInitGL(shadergl_t *shader, const shaderdefinitiongl_t *def) {
   assertNotNull(shader, "Shader cannot be null");
@@ -15,7 +21,11 @@ errorret_t shaderInitGL(shadergl_t *shader, const shaderdefinitiongl_t *def) {
   memoryZero(shader, sizeof(shadergl_t));
 
   #ifdef DUSK_OPENGL_LEGACY
-    // No initialization needed for legacy shader
+    glm_mat4_identity(shader->view);
+    glm_mat4_identity(shader->proj);
+    glm_mat4_identity(shader->model);
+
+    SHADER_LEGACY.boundShader = NULL;
     errorOk();
   #else
     // Create vertex shader
@@ -139,12 +149,16 @@ errorret_t shaderParamGetLocationGL(
   assertStrLenMin(name, 1, "Uniform name cannot be empty");
   assertNotNull(location, "Location cannot be null");
 
+  #ifdef DUSK_OPENGL_LEGACY
+    assertUnreachable("Cannot get uniform locations on legacy opengl.");
+  #else
     shadergl_t *shaderGL = (shadergl_t *)shader;
     *location = glGetUniformLocation(shaderGL->shaderProgramId, name);
     errorret_t err = errorGLCheck();
     if(err.code != ERROR_OK) {
       errorChain(err);
     }
+  #endif
   
   errorOk();
 }
@@ -152,27 +166,58 @@ errorret_t shaderParamGetLocationGL(
 errorret_t shaderSetMatrixGL(
   shadergl_t *shader,
   const char_t *name,
-  const mat4 mat
+  mat4 mat
 ) {
   assertNotNull(shader, "Shader cannot be null");
   assertNotNull(mat, "Matrix data cannot be null");
   assertStrLenMin(name, 1, "Uniform name cannot be empty");
 
+  #ifdef DUSK_OPENGL_LEGACY
+    assertTrue(
+      SHADER_LEGACY.boundShader == shader,
+      "Shader must be bound to set legacy matrices."
+    );
+    if(stringCompare(name, SHADER_UNLIT_PROJECTION) == 0) {
+      SHADER_LEGACY.dirty |= SHADER_LEGACY_DIRTY_PROJ;
+      glm_mat4_copy(mat, shader->proj);
+
+    } else if(stringCompare(name, SHADER_UNLIT_VIEW) == 0) {
+      SHADER_LEGACY.dirty |= SHADER_LEGACY_DIRTY_VIEW;
+      glm_mat4_copy(mat, shader->view);
+
+    } else if(stringCompare(name, SHADER_UNLIT_MODEL) == 0) {
+      SHADER_LEGACY.dirty |= SHADER_LEGACY_DIRTY_MODEL;
+      glm_mat4_copy(mat, shader->model);
+      
+    } else {
+      assertUnreachable("Cannot use a custom matrix on legacy opengl.");
+    }
+  #else
     GLint location;
     errorChain(shaderParamGetLocationGL(shader, name, &location));
 
     glUniformMatrix4fv(location, 1, GL_FALSE, (const GLfloat *)mat);
     errorChain(errorGLCheck());
+  #endif
 
   errorOk();
 }
 
 
 errorret_t shaderBindGL(shadergl_t *shader) {
+  #ifdef DUSK_OPENGL_LEGACY
+    assertNotNull(shader, "Cannot bind a null shader.");
+    SHADER_LEGACY.boundShader = shader;
+    SHADER_LEGACY.dirty = (
+      SHADER_LEGACY_DIRTY_MODEL |
+      SHADER_LEGACY_DIRTY_PROJ |
+      SHADER_LEGACY_DIRTY_VIEW
+    );
+  #else
     assertNotNull(shader, "Shader cannot be null");
-
     glUseProgram(shader->shaderProgramId);
     errorChain(errorGLCheck());
+  #endif
 
   errorOk();
 }
@@ -180,22 +225,58 @@ errorret_t shaderBindGL(shadergl_t *shader) {
 errorret_t shaderDisposeGL(shadergl_t *shader) {
   assertNotNull(shader, "Shader cannot be null");
 
+  #ifdef DUSK_OPENGL_LEGACY
+    SHADER_LEGACY.boundShader = NULL;
+  #else
     if(shader->shaderProgramId != 0) {
       glDeleteProgram(shader->shaderProgramId);
-    errorChain(errorGLCheck());
     }
     
     if(shader->vertexShaderId != 0) {
       glDeleteShader(shader->vertexShaderId);
-    errorChain(errorGLCheck());
     }
 
     if(shader->fragmentShaderId != 0) {
       glDeleteShader(shader->fragmentShaderId);
-    errorChain(errorGLCheck());
     }
 
     assertNoGLError("Failed disposing shader");
+  #endif
+
   memoryZero(shader, sizeof(shadergl_t));
   errorOk();
 }
+
+#ifdef DUSK_OPENGL_LEGACY
+  errorret_t shaderLegacyMatrixUpdate() {
+    assertNotNull(SHADER_LEGACY.boundShader, "No shader is currently bound.");
+
+    if((SHADER_LEGACY.dirty & SHADER_LEGACY_DIRTY_PROJ) != 0) {
+      glMatrixMode(GL_PROJECTION);
+      errorChain(errorGLCheck());
+      glLoadIdentity();
+      errorChain(errorGLCheck());
+      glMultMatrixf((const GLfloat *)SHADER_LEGACY.boundShader->proj);
+      errorChain(errorGLCheck());
+    }
+
+    if((SHADER_LEGACY.dirty & SHADER_LEGACY_DIRTY_VIEW) != 0) {
+      glMatrixMode(GL_MODELVIEW);
+      errorChain(errorGLCheck());
+      glLoadIdentity();
+      errorChain(errorGLCheck());
+      glMultMatrixf((const GLfloat *)SHADER_LEGACY.boundShader->view);
+      errorChain(errorGLCheck());
+    }
+
+    if((SHADER_LEGACY.dirty & SHADER_LEGACY_DIRTY_MODEL) != 0) {
+      glMatrixMode(GL_MODELVIEW);
+      errorChain(errorGLCheck());
+      glMultMatrixf((const GLfloat *)SHADER_LEGACY.boundShader->model);
+      errorChain(errorGLCheck());
+    }
+    
+    SHADER_LEGACY.dirty = 0;
+    errorOk();
+  }
+#endif

src/duskgl/display/shader/shadergl.h

@@ -16,6 +16,12 @@ typedef struct {
     GLuint vertexShaderId;
     GLuint fragmentShaderId;
   #endif
+
+  #if DUSK_OPENGL_LEGACY
+    mat4 view;
+    mat4 proj;
+    mat4 model;
+  #endif
 } shadergl_t;
 
 typedef struct {
@@ -27,6 +33,19 @@ typedef struct {
   #endif
 } shaderdefinitiongl_t;
 
+#if DUSK_OPENGL_LEGACY
+  typedef struct {
+    shadergl_t *boundShader;
+    uint_fast8_t dirty;
+  } shaderlegacygl_t;
+
+  extern shaderlegacygl_t SHADER_LEGACY;
+  
+  #define SHADER_LEGACY_DIRTY_PROJ (1 << 0)
+  #define SHADER_LEGACY_DIRTY_VIEW (1 << 1)
+  #define SHADER_LEGACY_DIRTY_MODEL (1 << 2)
+#endif
+
 /**
  * Initializes a shader.
  * 
@@ -69,7 +88,7 @@ errorret_t shaderParamGetLocationGL(
 errorret_t shaderSetMatrixGL(
   shadergl_t *shader,
   const char_t *name,
-  const mat4 matrix
+  mat4 matrix
 );
 
 /**
@@ -78,3 +97,13 @@ errorret_t shaderSetMatrixGL(
  * @param shader The shader to dispose.
  */
 errorret_t shaderDisposeGL(shadergl_t *shader);
+
+#ifdef DUSK_OPENGL_LEGACY
+  /**
+   * During mesh rendering, this is requesting the legacy system to push all
+   * shaders necessary to render the currently bound shader's matrices.
+   * 
+   * @return Any error state.
+   */
+  errorret_t shaderLegacyMatrixUpdate();
+#endif

src/duskgl/display/shader/shaderunlitgl.c

@@ -7,6 +7,9 @@
 
 #include "display/shader/shaderunlit.h"
 
+#ifdef DUSK_OPENGL_LEGACY
+  shaderdefinition_t SHADER_UNLIT_DEFINITION = { 0 };
+#else
   shaderdefinition_t SHADER_UNLIT_DEFINITION = {
     .vert =
       "#version 330 core\n"
@@ -25,3 +28,4 @@ shaderdefinition_t SHADER_UNLIT_DEFINITION = {
       "  FragColor = vec4(1.0, 0.0, 0.0, 1.0);\n" 
       "}\n"
   };
+#endif

src/dusksdl2/display/displaysdl2.c

@@ -24,8 +24,13 @@ errorret_t displaySDL2Init(void) {
   // SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
   // SDL_GL_SetAttribute(SDL_GL_STENCIL_SIZE, 8);
 
+  #ifdef DUSK_OPENGL_LEGACY
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_COMPATIBILITY);
+  #else
+    SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_CORE);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 3);
     SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 3);
+  #endif
 
   // Create window with OpenGL flag.
   DISPLAY.window = SDL_CreateWindow(